JP4610430B2 - Electric brake device - Google Patents

Description

  The present invention relates to an electric brake device that converts a rotational motion of a motor into a linear motion and presses a brake pad against a disk to generate a braking force, and a control method thereof, and more particularly, an electric brake device that can reduce heat generation and power consumption. And a control method thereof.

  In recent years, electric brake systems have been proposed that generate thrust by applying rotation of an electric motor based on an electric signal command in place of a hydraulic brake device. For example, in Patent Document 1, when the required thrust according to the driver's depression of the brake pedal when the vehicle is in a stopped state is larger than the thrust required to maintain the stopped state, the thrust is corrected to maintain the stopped state. Thus, an electric brake device that avoids unnecessary power consumption when the vehicle is stopped is described.

JP 2001-63537 A

  In the prior art described above, the thrust for maintaining the stop when the vehicle stops is detected, and the stop is maintained when the thrust corresponding to the driver's depression of the brake pedal is greater than the thrust for maintaining the stop. The thrust is corrected. For this reason, there is a possibility that the vehicle may start when the driver weakens the depression of the brake pedal even a little, and there is a problem that the driver must always maintain a certain amount of depression of the brake pedal above a certain level.

  In addition, when the vehicle is in a stopped state, for example, when the vehicle is loaded on a transportation vehicle such as a car carrier, there is a problem that the vehicle may start when the vehicle is inclined due to an external factor.

  The present invention relates to an electric brake capable of reducing power consumption due to useless thrust demand from the occupant when the vehicle is stopped after stopping a running vehicle by operating a brake pedal and suppressing heat generation associated therewith. It is in providing an apparatus and its control method. It is another object of the present invention to provide an electric brake device capable of maintaining a stopped state of a vehicle even when disturbance is applied, and a control method thereof.

  In order to achieve the above object, an electric brake device according to the present invention comprises thrust generating means for generating a thrust for converting a rotational motion of a motor into a linear motion and pressing a brake pad against a disc rotor, and a driver's brake pedal. The electric brake device generates a required thrust by a stepping operation of the vehicle, and the electric brake device calculates a thrust necessary to hold the stop of the vehicle, and adds a predetermined increment to the thrust. And a thrust control means for controlling the required thrust to be generated by limiting the required thrust to the target thrust.

  The electric brake device of the present invention configured as described above limits the maximum thrust so as not to apply more current than necessary to the motor that presses the brake pad against the disk rotor, thereby reducing current consumption and suppressing heat generation. be able to. Thereby, the fuel consumption rate of the vehicle can be improved. In addition, since the vehicle is stopped with a thrust obtained by adding a predetermined increment to the thrust necessary for stopping, stable braking performance can be ensured, and movement of the vehicle due to disturbance or the like can be prevented.

  Moreover, as a preferable specific aspect of the electric brake device according to the present invention, the electric brake device includes a vehicle weight detection unit that detects a vehicle weight including a driver, an occupant, and a load, and an inclination at a stop. Means for detecting a state, and the calculating means calculates the target thrust based on a vehicle weight detecting means and an inclination state detecting means. According to the electric brake device configured as described above, the vehicle weight is accurately detected, and the thrust necessary for stopping the vehicle is calculated from the vehicle weight and the vehicle inclination state. Can be stopped in a state, and the stopped state can be stably maintained.

  The electric brake device includes a thrust sensor that detects an actual thrust that the brake pad presses against the disk rotor, and a comparison unit that compares the actual thrust detected by the thrust sensor with a target thrust. Is characterized in that when the actual thrust is larger than the target thrust, the thrust generated by the thrust generating means is limited to the target thrust based on the target thrust. According to this configuration, when the driver depresses the brake pedal more than necessary, the thrust can be limited to reduce the current to the motor, and the power consumption can be suppressed to suppress heat generation.

  The electric brake device includes a parking brake means for maintaining a stopping state of the vehicle by holding a thrust force that presses the brake pad against the disk rotor by a lock mechanism, and the thrust control means is held by the parking brake means. It is preferable to limit the thrust to be performed to the target thrust. According to this configuration, the stop state can be stabilized when the vehicle is parked, and the vehicle can be prevented from moving even if a disturbance or the like is applied during parking.

  The predetermined increment added to the necessary thrust is preferably calculated based on the state of the brake pad. When the brake pads are worn, the braking force is reduced even if the disc rotor is pressed with the same thrust, so that the stop state of the vehicle can be ensured by setting the increment large. Further, it is preferable that the predetermined increment is calculated based on an output of the tilt state detecting means and / or the vehicle weight detecting means. Since the road surface where the vehicle is stopped has a large inclination angle and the weight is large, it is easy to move, so an increment is calculated according to the inclination angle and the vehicle weight, and the vehicle is stopped by limiting the target thrust to the increment. The state can be ensured.

  A control method for an electric brake device according to the present invention is a control method for an electric brake device that generates a thrust by pressing a brake pad against a disc rotor by a thrust requested by a driver's depression of a brake pedal. A thrust required to hold the stop is calculated, and a target thrust obtained by adding a predetermined increment to the thrust is calculated. When the required thrust is larger than the target thrust, a thrust corresponding to the target thrust It is characterized by generating. According to this configuration, since the maximum thrust is limited so as not to apply more current than necessary to the motor of the thrust generating means, current consumption can be reduced, heat generation can be suppressed, and the fuel consumption rate of the vehicle is improved. be able to. In addition, stable braking performance can be ensured, and movement of the vehicle due to disturbance or the like can be prevented.

  The electric brake device of the present invention and the control method thereof detect the state where the vehicle is stopped on the vehicle side when the vehicle is stopped, and determine the maximum thrust generated by the driver's brake pedal operation. By limiting to the target thrust obtained by adding a predetermined increment to the thrust required to stop the vehicle, power consumption can be reduced, heat generation can be suppressed, and the fuel consumption rate of the vehicle can be increased. In addition, the vehicle stop state can be stabilized.

  Hereinafter, an embodiment of an electric brake device according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a configuration diagram of an electric brake device according to the present embodiment, and FIG. 2 is a block diagram showing an internal configuration of the electric brake controller 3 of FIG. 1 in FIG.

  In FIG. 1, the electric brake device B includes a stroke sensor 2 that detects the amount of depression when the driver depresses the brake pedal 1. The output of the stroke sensor 2 is input to the electric brake controller 3, which outputs a thrust command corresponding to the driver's brake pedal 1 depression amount, and rotates the motor M in the caliper 4. The motor M rotates, and the piston is propelled through a conversion mechanism that converts the rotational motion into a linear motion, and the brake pads 5 and 5 generate a braking force by thrust thrusting the disc rotor 6 by the piston. Although not shown in the figure, a ball ramp mechanism, a ball screw mechanism, or the like is used as a conversion mechanism that converts rotational motion into linear motion. The motor M and the conversion mechanism constitute thrust generating means. Therefore, the electric brake device B generates a thrust according to the brake operation.

  Inside the caliper 4, a thrust sensor 7 for detecting a thrust generated by the brake pads 5 and 5 sandwiching the disc rotor 6 is incorporated. Further, a wheel speed sensor 8 for detecting the rotational speed of the wheel is incorporated in the caliper 4. The electric brake controller 3 includes a detection result of the wheel speed sensor 8 that monitors the rotation of the wheel, a vehicle weight sensor 9 that detects the vehicle weight of the vehicle, and G that detects vehicle vibration, acceleration at the start of the vehicle, and an inclination state. A signal from the sensor 10 is input.

  A parking brake 11 is installed separately from the caliper 4 on the outer periphery of the disc rotor 6. The parking brake 11 may be manually operated by the driver or electrically operated using a motor. The parking brake 11 obtains a braking force by pressing the brake pads 12 and 12 against the disc rotor 6 by a motor M1 constituting thrust generating means arranged in a caliper different from the caliper 4, A parking brake (PKB) thrust sensor 13 for detecting the thrust generated by the parking brake operation and a parking brake (PKB) operation sensor 14 for detecting the operating state of the parking brake are incorporated, and the parking brake operation switch (PKBSW) 15 The operation signal is input to the electric brake controller 3 to be operated. The parking brake of the present embodiment is configured as an electric parking brake that is separate from the caliper 4 that stops the running vehicle.

  And the signal from the parking brake thrust sensor 13 which detects the thrust which the parking brake 11 has generate | occur | produced at the time of parking brake operation | movement, and the parking brake operation sensor 14 which detects the operating state of the parking brake 11 is input into the electric brake controller 3. And constantly monitor the condition of the vehicle. From the above detection results, the electric brake controller 3 can detect whether the vehicle is running or stopped.

  The electric brake device B of the present embodiment is configured such that the electric brake caliper 4 and the parking brake 11 are independent from each other, but the function of the parking brake 11 is added to the electric brake caliper 4. Some are integrated. In the integrated electric brake device, the parking brake functions as a parking brake by holding the thrust generated by pressing the brake pad against the disc rotor by the lock mechanism. A ratchet mechanism or the like can be used as the lock mechanism.

  When the driver depresses the brake pedal, power consumption and heat generation become a problem when the driver depresses the maximum thrust in a short time and continuously depresses the brake pedal. In order to reduce the increase in power consumption and heat generation caused by the driver's depression of the brake pedal, the maximum thrust limit is performed.

  In FIG. 2, the electric brake controller 3 detects a power supply unit 21 to which power such as a battery is supplied, a motor driver unit 22 that supplies a drive current to the motor M in the caliper 4, and a current supplied to the motor M. Motor current detecting unit 23 for receiving, an electric brake side interface unit 24 for receiving signals from wheel speed sensors and thrust sensors, and a vehicle side interface for receiving outputs from a vehicle weight sensor, a G sensor, etc. installed on the vehicle side The unit 25 and an arithmetic unit 26 that calculates based on various inputs. The motor driver unit 22 constitutes thrust control means of the electric brake device.

  Hereafter, each said part is demonstrated in detail. The power supply unit 21 supplies power to each block constituting the electric brake controller 3 from a battery (not shown). The motor driver unit 22 performs motor control necessary for the caliper 4 to generate a required thrust force by the driver pressing the brake pedal 1. That is, the braking force can be generated by rotating the motor M in the forward direction, and the braking force can be loosened by rotating in the reverse direction.

  The motor current detector 23 detects a current value consumed by the motor M inside the caliper 4 and detects an abnormality such as an overcurrent. In the electric brake side interface section 24, if the detection signal from the thrust sensor 7 inside the caliper 4 or the electric brake with a built-in parking brake function, the parking brake control is performed. The vehicle-side interface unit 25 includes information on brake pedal depression by the driver from the stroke sensor 2 shown in FIG. 1, signal input from the vehicle weight sensor 9, G sensor (tilt sensor) 10, wheel speed sensor 8, The thrust value information in the electric brake device B and the normal operation and abnormal operation of the electric brake device B are transmitted and received by signals.

  In the arithmetic unit 26, monitoring of the output voltage from the power supply unit 21, input signal processing from the vehicle, signal output to the vehicle, control of the motor driver unit 22, monitoring of motor current consumption by signals from the motor current detection unit 23, The generated thrust value at the caliper 4 is detected. Further, the arithmetic unit 26 calculates a necessary thrust F0 for generating a braking force necessary for maintaining the stop of the vehicle equipped with the electric brake device B, and calculates a predetermined increment α with respect to this thrust. Means for calculating the added target thrust F1 is provided, and the electric brake controller 3 performs a maximum thrust limiting process for limiting the braking force generated from the electric brake device B to the target thrust F1.

  The maximum thrust limit of the present invention is the vehicle speed detection signal from the vehicle side interface unit 25 and the wheel speed sensor 8 input from the electric brake side interface unit 24, the detection signal from the vehicle weight sensor 9, the detection signal from the G sensor 10, and the thrust sensor. The thrust value necessary for the vehicle to stop is calculated from the detection signal 7 and the operation information of the parking brake 11, and the maximum thrust limit is performed. Hereinafter, the maximum thrust control method will be described.

First, the thrust F0 necessary for stopping the vehicle is calculated from the weight W of the vehicle and the inclination angle θ of the road surface on which the vehicle is stopped. The weight W of the vehicle uses the output of the vehicle weight sensor 9 and includes the weight of the vehicle itself and the weight of the passenger on board or the weight of the loaded luggage. Further, a detection signal of the G sensor 10 is used for the inclination angle θ. That is, the necessary thrust F0 is calculated from the following mathematical formula (1).
Necessary thrust, F0 = Wsinθ (1)

Then, the arithmetic unit 26 calculates a target thrust F1 obtained by adding a predetermined increment α to the required thrust F0 obtained from the following formula (2).
Target thrust, F1 = Wsin θ + α (2)

  The predetermined increment α is preferably set in accordance with the inclination state of the road surface on which the vehicle is stopped. That is, when the vehicle is stopped on the road surface with the inclination angle θ, it is preferable to set α = k · sin θ (k is a proportional coefficient) because the increase α becomes large when the inclination angle is large. Further, when the wear amount of the brake pad is equal to or greater than a predetermined amount, the proportionality constant is set to be larger than that when the brake pad is new. The proportionality coefficient is preferably about 5 to 20% of the vehicle weight W.

  Therefore, the vehicle equipped with the electric brake device B is maximum so that the electric brake controller 3 is stopped with a braking force corresponding to the target thrust F1 that is larger by α than the necessary thrust F0 that can maintain the stopped state. A thrust control process is performed, and a current corresponding to the added target thrust F1 is output from the motor driver unit 22. This motor driver unit uses the target thrust F1 obtained by adding a predetermined increment α to the necessary thrust F0 and the brake pad 5 , 5 presses the disk rotor 6 and controls the motor M constituting the thrust generating means to rotate.

  FIG. 3 is a flowchart of the maximum thrust limiting process executed by the electric brake controller 3 when the traveling vehicle is stopped by the driver's brake pedal operation and the vehicle is kept stopped only by the driver's brake pedal operation. Indicates.

  The thrust limiting process (S1) performs vehicle speed information detection (S2) from information detected by the wheel speed sensor 8 in FIG. If the wheel speed sensor 8 determines that the vehicle speed has become “0” (S4) and the vehicle has stopped due to the driver's depression of the brake pedal (S3), the actual thrust required to stop the vehicle with the thrust sensor 7 Is detected and the electric brake controller 3 limits the maximum thrust (S5 to S8).

  The maximum thrust limit (S5 to S8) is obtained by setting a predetermined increment α with respect to the actual thrust F actually stopped by the thrust sensor 7 and the thrust F0 necessary for maintaining the vehicle in a stopped state. The comparison is made with the added target thrust F1. That is, the arithmetic unit 26 of the electric brake controller 3 calculates the thrust F0 necessary for stopping the vehicle from the stop state of the vehicle (S5). For example, when the vehicle is stopped on a flat road surface, the required thrust is set small, and when the vehicle is stopped on an inclined surface, the necessary thrust is set large according to the inclination angle θ, and the vehicle weight is large. Sometimes the required thrust is set even greater. Here, the necessary thrust F0 is calculated as F0 = Wsin θ by the above equation (1).

  The electric brake controller 3 calculates the target thrust F1 obtained by adding a predetermined increment α to the calculated necessary thrust F0 as F1 = Wsin θ + α in the above equation (2) (S6). Then, the actual thrust F detected by the thrust sensor 7 and the target thrust F1 are compared (S7). If the actual thrust F is larger than the target thrust F1, the target thrust F1 is replaced with the actual thrust F in S8. The current value corresponding to the target thrust is output to the motor driver unit 22, and the motor driver unit 22 outputs a current value that can be generated by the motor M to the motor M with the thrust added with a predetermined increment α. When a current is applied to the motor M, the rotor rotates. This rotation is converted into a linear motion by the conversion mechanism, and the brake pads 5 and 5 press the disc rotor 6 to generate a braking force.

  In this case, since the motor M is driven with a current value that generates a target thrust F1 smaller than the actual thrust F, current consumption can be reduced and heat generation of the caliper 4 can be prevented. Moreover, since the target thrust F1 is set larger than the minimum thrust F0 necessary for stopping the vehicle by the increment α, the vehicle stop state is stable, and even if a disturbance or the like acts on the vehicle, the vehicle Never move. If the actual thrust F is equal to or smaller than the target thrust F1 in S7, the process directly returns.

  In the electric brake device B of the present embodiment, the arithmetic unit 26 of the electric brake controller 3 calculates a thrust F0 necessary for stopping the vehicle, and adds a predetermined increment α to the thrust F0 to obtain a target thrust F1. Therefore, the current value applied to the motor M can be suppressed, and the power consumption can be reduced. Thereby, heat generation in the caliper 4 can be prevented and stable braking performance can be exhibited. In addition, the target thrust is set larger than the necessary thrust by the increment α, and the vehicle can be prevented from moving due to the influence of disturbance or the like.

  The increment α is changed according to the state where the vehicle is stopped as described above, and is also changed according to the state of the brake pad. For example, even if the brake pedal depression amount is the same and the generated thrust is the same, a large braking force is generated when the brake pad is new, and a small braking force is generated when worn. Let In this case, when the wear amount is within a predetermined range, a certain increment is added, and when the wear amount is more than a certain value, that is, when the remaining amount is less than a certain value, the increment is changed. The increment of the thrust may be set so as to be increased by, for example, 10% when the wear amount is a certain amount or more.

  Thereby, wasteful power consumption and heat generation can be suppressed by limiting the maximum thrust in response to a thrust request more than necessary due to depression of the brake pedal from the driver. When the brake pedal is released by the driver (S9), the maximum thrust limit is released and the target thrust is set to “0” (S10). Note that the maximum thrust restriction release (S10) may be performed when the wheel speed sensor 8 determines that the vehicle has started again, instead of the brake pedal release.

  FIG. 4 shows the generated thrust with respect to the driver's brake pedal depression amount when the maximum thrust limiting process is performed according to the flowchart of FIG. In the maximum thrust limiting process, the thrust required for the driver to stop the vehicle is detected by the thrust sensor 7 by depressing the brake pedal, and the thrust value is set when the maximum thrust is limited based on the thrust value.

  When the maximum thrust is limited, the electric brake controller uses the actual thrust F detected by the driver's brake pedal depression detected by the thrust sensor 7 and the target thrust F1 obtained by adding a predetermined increment α to the thrust F0 required for stopping the vehicle. When the actual thrust F is larger than the target thrust F1, a thrust corresponding to the smaller target thrust is generated. The maximum thrust limiting process makes it possible to suppress power consumption and heat generation in response to a thrust request more than necessary due to the driver's depressing of the brake pedal more than necessary, and even if a disturbance or the like acts on a stopped vehicle Since the vehicle is stopped at the target thrust F1 obtained by adding the predetermined increment α, the stop state of the vehicle can be stabilized.

  The description based on FIG. 3 and FIG. 4 described above is the maximum thrust limiting control in the case where the traveling vehicle stops by the driver's brake pedal operation and the vehicle's stop state is maintained only by the driver's brake pedal operation. . This also applies to the electric brake device B in which the caliper 4 for the electric brake and the parking brake 11 are independent and the electric brake device in which the caliper 4 for the electric brake also has a parking brake function. It can be controlled by the controller 3.

  FIG. 5 shows a maximum thrust limiting process (S11) executed by the electric brake controller 3 when the running vehicle is stopped by the driver's brake pedal operation and then the driver's parking brake operation is maintained. ) Is shown.

  When the vehicle travels, vehicle speed information detection (S12) is always performed by the wheel speed sensor 8. When the electric brake controller 3 detects that the vehicle has been stopped by the driver's operation of depressing the brake pedal and the vehicle speed becomes “0” (S13), and the driver has pressed the parking brake operation switch 15 and operated the parking brake (S14). Maximum thrust restriction is started (S15). This maximum thrust limit is equivalent to the target thrust by calculating a target thrust obtained by adding a predetermined increment β to the thrust required to maintain the vehicle in a stopped state, as in S5 and S6 of FIG. A current is output from the motor driver unit, and a braking force slightly larger than the required thrust is generated by the rotation of the motor M1. Since the vehicle is stopped with a braking force corresponding to a target thrust larger than the necessary thrust, the stopped state can be maintained and the stopped state can be maintained even if a disturbance or the like is applied. Thereafter, the driver releases the parking brake 11 (S16), so that the maximum thrust restriction is released (S17).

  Next, two processing methods for limiting the maximum thrust will be described in accordance with the parking brake operation flowchart shown in FIG.

  First, the first processing method will be described below with reference to FIGS. FIG. 6 shows a thrust value applied to the disc rotor 6 when the parking brake is operated. During the parking brake operation, a constant parking thrust F2 is applied to the disc rotor 6 regardless of the driver's brake pedal depression operation, and the vehicle is kept stopped. In this case, the maximum thrust restriction is performed on the thrust generated when the driver depresses the brake pedal.

  FIG. 7 shows the thrust applied to the disc rotor with respect to the brake pedal depression amount of the driver when the maximum thrust is limited. The maximum thrust that the driver applies to the disc rotor by operating the brake pedal is limited to be smaller than the thrust value that the parking brake applies to the disc rotor, and is set to increment β. Thus, the brake from the driver is limited by limiting the maximum thrust to the target thrust F3 (see FIG. 8) obtained by adding the increment β to the thrust required to stop the vehicle with respect to the constant parking thrust F2. It is possible to suppress power consumption and heat generation in response to a useless thrust request due to depression of the pedal, and the stop state is stabilized.

  FIG. 8 shows the thrust applied to the disc rotor when the driver of FIG. 7 performs the depression of the brake pedal during the parking brake operation shown in FIG. In this case, the thrust F3 applied to the disc rotor 6 is a value obtained by adding the parking thrust F2 in which the parking brake is generated and the increment β by the driver's brake pedal operation. For this reason, even when a disturbance or the like acts on the vehicle during the parking brake operation, the vehicle can be prevented from moving, and the vehicle can be stopped stably.

  The second processing method will be described below with reference to FIG. Also in this processing method, as in the first processing method, the maximum thrust limiting process is performed for the driver's brake pedal depression operation. FIG. 9 shows the thrust applied to the disc rotor when the driver depresses the brake pedal when the maximum thrust is limited.

  The maximum thrust applied to the disc rotor by the driver operating the brake pedal is limited to a thrust value equal to or greater than the thrust applied to the disc rotor by the parking brake operation. That is, a thrust obtained by adding a thrust necessary for stopping the vehicle and a predetermined increment γ to the parking brake generated thrust F4 is set as a target thrust F5. By this method, the thrust generated is limited to the target thrust F5 in response to a thrust request more than necessary due to the depression of the brake pedal from the driver, so that it is possible to suppress power consumption and heat generation consumed by the parking brake 11. Become. Further, the target thrust F5 is obtained by adding the thrust necessary for stopping the vehicle and the increment γ, and the stop state is stabilized.

  This maximum thrust limit processing method is based on the thrust required to stop the vehicle even when an external force is applied to the vehicle due to some trouble even when the parking brake is operated, or even when the maximum thrust limit is not released. Also, since it is possible to generate a thrust that is larger by the increment γ, the vehicle can be stopped in a stable state.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various designs can be made without departing from the spirit of the present invention described in the claims. It can be changed. For example, the brake pad is configured to be sandwiched between a pair of brake pads from both sides of the disk rotor, but may be configured to be sandwiched between two pairs of brake pads. Moreover, although the example of G sensor was shown as a means to detect the inclination state of a vehicle, of course, you may use the inclination sensor which is not restricted to G sensor.

  In the above-described embodiment, an example of an electric brake that is separate from the caliper unit as a parking brake has been shown. However, a brake pad is generated against the disc rotor by a motor in the caliper unit via a conversion mechanism to generate a braking force. A built-in parking brake configured to hold the braking force using a mechanism or the like may be used. The built-in parking brake can be simplified in configuration as compared with a separate parking brake.

  As an example of using the output from the thrust sensor as the actual thrust to be compared with the target thrust, the actual thrust is calculated using the output from the stroke sensor of the brake pedal. You may comprise so that the made actual thrust and target thrust may be compared. Thus, when the actual thrust that the brake pad actually presses the disk rotor is calculated using the stroke sensor, the thrust sensor can be omitted, and the configuration can be simplified.

  As an application example of the present invention, the use of this electric brake device can be applied to the use of a brake device such as a railway vehicle or an aircraft.

The block diagram which shows the electric brake device of one Embodiment of this invention. The block diagram which shows the internal structure of the electric brake controller of FIG. The flowchart which shows the maximum thrust restriction | limiting process in the vehicle stop maintenance state by the driver | operator's brake pedal operation of this invention. Explanatory drawing which showed the target thrust with respect to the depression amount of the brake pedal at the time of the maximum thrust restriction | limiting in FIG. The flowchart which shows the maximum thrust limitation process in the vehicle stop maintenance state by the driver | operator's parking brake operation of this invention. Explanatory drawing which showed the parking brake generation | occurrence | production thrust value in the maximum thrust restriction | limiting process method 1 in FIG. FIG. 6 is an explanatory diagram showing a generated thrust value with respect to an amount of depression of a brake pedal in the maximum thrust limit processing method 1 in FIG. 5. FIG. 6 is an explanatory diagram showing a target thrust applied to the disk rotor in the maximum thrust restriction processing method 1 in FIG. 5. FIG. 6 is an explanatory diagram showing a target thrust with respect to a brake pedal depression amount in the maximum thrust restriction processing method 2 in FIG. 5.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Brake pedal, 2 ... Stroke sensor, 3 ... Electric brake controller, 4 ... Caliper, 5 ... Brake pad, 6 ... Disc rotor, 7 ... Thrust sensor, 8 ... Wheel speed sensor, 9 ... Vehicle weight sensor, 10 ... G Sensor (tilt sensor), 11 ... parking brake (separate electric parking brake), 12 ... brake pad, 13 ... parking brake thrust sensor, 14 ... parking brake operation sensor, 15 ... parking brake operation switch, 21 ... power supply unit, DESCRIPTION OF SYMBOLS 22 ... Motor driver part (thrust control means), 23 ... Motor current detection part, 24 ... Electric brake side interface, 25 ... Vehicle side interface part, 26 ... Calculation apparatus part (calculation means), B ... Electric brake apparatus, F ... Actual thrust, F0: necessary thrust, F1, F3, F5 ... target thrust, F2, F4: parking thrust, α: predetermined increment, β, γ Predetermined increment that contains the required thrust

Claims (4)

A thrust generating means for generating a thrust for generating a braking force on a disc rotor provided on the wheel; and an electric brake controller for controlling the thrust of the thrust generating means,
The thrust generation means includes a brake pad that presses the disc rotor to generate a braking force, a motor, and a mechanism that converts the rotational motion of the motor into a linear motion and applies a thrust to the brake pad to generate the braking force. Have
The electric brake controller has an electric brake side interface unit for receiving a signal from a sensor and a motor drive unit for controlling a supply current to the motor,
The electric brake controller obtains an actual thrust F generated to stop the vehicle based on a brake operation,
The electric brake controller calculates a target thrust F1 obtained by adding a predetermined increment to a necessary thrust F0 for maintaining the stop of the vehicle,
When the actual thrust F is greater than the target thrust F1, the electric brake controller controls the supply current to the motor based on the target thrust F1 instead of the actual thrust F in order to maintain the vehicle stopped state. An electric brake device characterized by that. In the electric brake device according to claim 1,
The thrust generating means has a thrust sensor for detecting the thrust actually generated,
The electric brake controller receives a signal representing a weight of the vehicle, a signal representing a leaning state of the vehicle in a stopped state, and an output signal of the thrust sensor,
The electric brake controller calculates the target thrust F1 based on a signal representing the weight and a signal representing the lean state of the vehicle,
The electric brake controller further obtains the actual thrust F from the output signal of the thrust sensor. When the actual thrust F is larger than the target thrust F1, the electric brake controller replaces the actual thrust F in order to maintain a vehicle stop state. The electric brake device is characterized in that the current supplied to the motor is controlled based on the target thrust F1. In the electric brake device according to claim 1 or 2,
The electric brake controller compares the actual thrust F with the target thrust F1,
In the state where the actual thrust F is larger than the target thrust F1, the supply current to the motor is controlled based on the target thrust F1 instead of the actual thrust F in order to keep the vehicle stopped.
In the state where the actual thrust F is smaller than the target thrust F1, the electric brake device is characterized in that the current supplied to the motor is controlled by the actual thrust F in order to maintain the stop state of the vehicle. The electric brake device includes parking brake means for maintaining a stop state of the vehicle by holding a thrust force that presses the brake pad against the disc rotor by a lock mechanism.
The electric brake device according to any one of claims 1 to 3, wherein the thrust control means limits the thrust held by the parking brake means to the target thrust.

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