JP6545584B2 - Electric brake device - Google Patents

Description

  The present invention relates to an electric brake device, and relates to a technique for adjusting a clearance amount without giving a sense of discomfort to a driver in a vehicle equipped with the electric brake device.

  In vehicles equipped with an electric brake that can freely determine the amount of clearance between the brake disc and the brake pad, various proposals have been made for adjusting the amount of clearance. When driving a vehicle, it is desirable to increase the amount of clearance to eliminate drag on the brake, and reduce the amount of clearance before braking to prevent noise and to prevent response delay, and change the clearance even in a brake using a hydraulic system. Possible structures have been proposed.

  In a structure in which the amount of clearance can be adjusted by a conventional brake using a hydraulic system, for example, negative pressure is generated in the hydraulic system when drag on the brake is unnecessary, and the amount of clearance is increased during traveling to Relieve drag (Patent Document 1). Thus, it can be seen that reducing drag is a permanent issue in the braking of vehicles, and unnecessary drag should also be reduced in an electric brake.

  In the case of the electric brake, the noise generated at the time of adjusting the clearance amount can not be avoided, which is also a cause of discomfort. Therefore, the clearance is adjusted to shorten the time during which unnecessary brake drag occurs, but the adjustment is performed at such a timing as to reduce the driver's discomfort, which leaves room for reducing the noise of the electric brake noise. was there.

In an electric brake that can freely determine the amount of clearance between the brake disc and the brake pad, a technique for determining the amount of clearance and maintaining the amount of clearance is disclosed (Patent Document 2). In this patent document 2, the clearance is determined on the basis of the position pushed back by the reaction force from the brake disc to the brake pad, with respect to the relationship between the actuator position and the clearance which changes due to the wear of the brake disc and the brake pad. Among them, it is pointed out that if the clearance is increased, the free running time is increased and the responsiveness is reduced.
From these, it is understood that it is important to secure responsiveness while reducing dragging.

JP, 2010-215188, A Unexamined-Japanese-Patent No. 2010-203561 Japanese Patent Laid-Open No. 2002-67906 JP 11-165620 A

However, in the electric brake, noise is generated when the actuator is operated, there is a high possibility that the driver may feel discomfort, and also generated when adjusting the clearance amount. Also, this noise has been a hindrance to the spread of electric brakes.
Based on such knowledge, Patent Document 3 shows a technique for determining the operating speed of the actuator when reducing the amount of clearance for pressure generation and bringing the brake disc and the brake pad into contact with each other (i.e., reducing the clearance). There is. In Patent Document 3, when traveling at high speed where the traveling noise becomes large, the actuator is operated at high speed with emphasis on responsiveness, and at low speed traveling when noise of the actuator is easily noticeable, the actuator is operated at low speed.

The above-mentioned contents were mainly aimed at the structure and control method which can adjust the clearance, and the alleviation of the sound at the time of the clearance adjustment.
Although it is desirable to provide an electric brake completely free of noise by combining these, its realization is difficult. However, there is room to take a method to reduce the sense of incongruity by performing control and operation with noise at timing when the driver hardly notices the noise.

It is necessary to change the clearance when the brake pedal is not operated. When the brake pedal is not operated, the clearance should be optimally changed in accordance with the traveling state of the vehicle and the driver's input, so that control should be performed so as not to notice noise and not to deteriorate responsiveness.
On the other hand, when the brake pedal is operated, the clearance is immediately filled, and pressing is generated according to the operation amount of the brake pedal, but the clearance amount is always zero, and control for changing the clearance is unnecessary.

  An object of the present invention is to provide an electric brake device capable of adjusting the amount of clearance without giving a sense of discomfort to a driver when the brake operation means is not operated in a vehicle equipped with the electric brake device.

The electric brake system according to the present invention uses the accelerator operation amount of the accelerator operation means and the vehicle speed as the basis of these situation determinations.
In the electric brake device according to the present invention, the rotary member 3, the friction members 4 and 4 to be brought into contact with the rotary member 3, and the friction member operation to bring the friction members 4 and 4 into contact with the rotary member 3 to generate a braking force. Control device 2 capable of adjusting a clearance amount which is a gap between the rotating member 3 and the friction member 4 by controlling the electric motor 6 for driving the friction member operating means 5 and the electric motor 6; And an electric brake device comprising
The vehicle equipped with this electric brake system is
A vehicle speed detection unit 9 that detects a vehicle speed;
10 for detecting an accelerator operation amount of the accelerator operation means 12;
And a brake operation amount detection unit 11 for detecting a brake operation amount of the brake operation means 13;
The control device 2 is
The vehicle speed detected by the vehicle speed detection unit 9 and the accelerator operation detected by the accelerator operation amount detection unit 10 when the brake operation amount of the brake operation unit 13 is not detected by the brake operation amount detection unit 11 Monitoring means 14 for monitoring the quantity;
And a clearance changing unit configured to change the amount of clearance when any one or both of the vehicle speed and the accelerator operation amount monitored by the monitoring unit satisfy the set condition.
The set conditions are determined by the results of tests and simulations.

  According to this configuration, the monitoring means 14 monitors the vehicle speed detected by the vehicle speed detection unit 9 and the accelerator operation amount detected by the accelerator operation amount detection unit 10 when the brake is not operated. The clearance changing means 15 changes the amount of clearance when one or both of the monitored vehicle speed and the amount of accelerator operation satisfy the set conditions. If there is a clear acceleration intention, and during the subsequent cruise, there should be input of a certain amount or more of the accelerator operation while increasing or decreasing the vehicle speed by operating the accelerator operation means 12 strongly. .

  If such a feature can be seen from the monitored vehicle speed or accelerator operation amount when the brake is not operated, the clearance amount is changed. When the vehicle speed increases, road noise that increases the noise level around the vehicle makes it difficult to notice noise associated with the change in the amount of clearance even if the amount of clearance is changed. Even when there is an input of an accelerator operation amount of a certain level or more, noise caused by the change of the clearance amount becomes difficult to notice even if the clearance amount is changed due to the noise of the engine or motor generated by the acceleration of the vehicle. Therefore, when the brake operation means 13 is not operated, the amount of clearance can be adjusted without giving a sense of discomfort to the driver.

  From the point of view of protection of each part and reduction of discomfort, generation of drag torque due to contact between the rotating member (brake disc) and the friction member (brake pad) while the vehicle is traveling should be suppressed. In particular, dragging is not necessary during acceleration or cruising, and dragging during long cruising may cause the brakes to overheat.

On the other hand, at the start of braking, sudden rise in braking torque and noise often occur when the clearance is made small and in contact. In order to improve the sensitivity performance, the clearance is set narrow, and if necessary, dragging It should be set to the accompanying value. It is preferable that a sufficiently narrow clearance can be maintained without dragging, but it is difficult for the brake pad to maintain the neutral position, and as shown in Patent Document 4, the characteristics differ between the pressure side and the pressure side. , Hard to achieve.
Therefore, we would like to improve the sensitivity performance by keeping the clearance open while driving and closing the clearance at the time of braking.

The clearance changing means 15
A target clearance determination unit that determines a target clearance that is a target value of the clearance amount;
A clearance amount adjustment unit 17 may be provided to adjust an actual clearance amount so as to match the target clearance determined by the target clearance determination unit 16.
In this case, after the target clearance determination unit 16 determines the target clearance, the clearance amount adjustment unit 17 adjusts the actual clearance amount so as to match the determined target clearance, thereby achieving the desired clearance amount. be able to.

The target clearance determination unit 16 sets the target clearance to an enlarged state larger than a predetermined proximity state when the accelerator operation amount monitored by the monitoring unit 14 exceeds the threshold A _H. It is good also as what has 16a.
The threshold value A _H , the proximity state, and the enlargement state are respectively determined by results of tests, simulations, and the like. When the accelerator operation amount exceeds the threshold value A _H, satisfying that the setting of the accelerator operation amount.

According to this configuration, for example, the accelerator operation amount is smaller than value frequently used in such an acceleration after the signal stops, the threshold value A _H to enlarge the target clearance. The clearance determination unit 16 a may reduce the drag between the rotating member 3 and the friction member 4 by expanding the target clearance to the enlarged state when the monitored amount of accelerator operation exceeds the threshold A _H. it can. This can improve the fuel efficiency of the vehicle.

The target clearance determination unit 16 sets the target clearance smaller than a predetermined expansion state when the accelerator operation amount monitored by the monitoring unit 14 falls below the threshold A _L. It is good also as what has 16a.
The threshold value _AL is determined by the result of a test, a simulation or the like.
In this case, the clearance determination unit 16a can prepare for braking by reducing the target clearance to the close state when the monitored amount of accelerator operation falls below the threshold value A _L. As a result, the sensitivity performance can be improved.

The target clearance determining unit 16 sets a threshold A _H used when the target clearance is expanded to be larger than a proximity state, and a threshold A _L used when the target clearance is reduced from the enlargement state to the proximity state. A difference may be provided to make the time for maintaining the expansion state longer than the time for maintaining the proximity state.
The "difference" between the threshold value A _H and the threshold value A _L often appears at the time of vehicle cruise, accelerator operation for finely adjusting the vehicle speed while securing the accelerator operation amount so that the vehicle speed does not decrease too much The target clearance is a relatively large difference which can prevent hunting, in which the proximity state and the expansion state are switched many times in a short time, which is determined by the result of a test, a simulation, or the like.

  The electric brake device according to the present invention comprises a rotating member, a friction member contacting the rotating member, friction member operating means for causing the friction member to contact the rotating member to generate a braking force, and the friction member operating means In an electric brake device comprising an electric motor to be driven and a control device capable of adjusting a clearance amount which is a gap between the rotating member and the friction member by controlling the electric motor, the electric brake device is mounted The vehicle includes a vehicle speed detection unit that detects a vehicle speed, an accelerator operation amount detection unit that detects an accelerator operation amount of the accelerator operation unit, and a brake operation amount detection unit that detects a brake operation amount of the brake operation unit. The control device is configured such that the brake operation amount detection unit does not detect the brake operation amount of the brake operation unit when the brake is not operated; Monitoring means for monitoring the vehicle speed detected by the vehicle speed detection unit and the accelerator operation amount detected by the accelerator operation amount detection unit, and one or both of the vehicle speed and the accelerator operation amount monitored by the monitoring means And clearance changing means for changing the amount of clearance when the set conditions are satisfied. Therefore, in a vehicle equipped with the electric brake device, the clearance amount can be adjusted without giving a sense of discomfort to the driver when the brake operation means is not operated.

It is a side view showing an electric brake actuator in an electric brake device concerning an embodiment of this invention. It is a block diagram of the control system of the same electric brake device. In a vehicle equipped with the same electric brake device, it is a figure showing an example of transition of an accelerator pedal operation amount and a vehicle speed. It is a figure which shows the other example of transition of the accelerator pedal operation amount and the vehicle speed. It is a flowchart which performs determination of the clearance opening of the same electric brake device. It is a flowchart which determines the clearance closing of the same electric brake device. The vehicle equipped with the electrically-driven brake device which concerns on other embodiment of this invention WHEREIN: It is a figure which shows the example of transition of an accelerator pedal operation amount and vehicle speed. It is a figure which shows the other example of transition of the accelerator pedal operation amount and the vehicle speed. It is a flowchart which performs determination of the clearance opening of the same electric brake device.

An electric brake device according to an embodiment of the present invention will be described with reference to FIGS. 1 to 6.
As shown in FIG. 1, the electric brake device has an electric brake actuator 1 and a control device 2. First, the electric brake actuator 1 will be described.
The electric brake actuator 1 includes a brake rotor 3 which is a rotating member, and a pair of friction members 4 disposed so as to sandwich the brake rotor 3. The friction member 4 comprises a friction pad. The brake rotor 3 consists of a brake disc in this example, and rotates integrally with a wheel not shown. The brake rotor 3 may consist of a brake drum.

  The electric brake actuator 1 includes a friction member operating means 5 that brings the friction member 4 into contact with the brake rotor 3 to generate a braking force, and an electric motor 6 that drives the friction member operating means 5. The electric motor 6 is composed of an AC motor such as a three-phase synchronous motor or an induction motor or a DC motor.

  The friction member operating means 5 is constituted by a linear movement mechanism or the like for converting a rotational input inputted from the electric motor 6 through the reduction mechanism 8 into a reciprocating linear motion of one of the friction members 4, and the brake rotor 3 in the caliper body 7. It is installed in one opposing part 7a which sandwiches. One friction member 4 is attached to the tip of the friction member operating means 5, and the other friction member 4 is attached to the other facing portion 7 b of the caliper pod 7. The caliper pody 7 is installed movably in the axial direction of the brake rotor 3 with respect to a mount (not shown) fixed to a knuckle (not shown) supporting the wheels.

The control device 2 and the like will be described.
Electric power is supplied to the electric motor 6 and the control device 2 from a power supply device (not shown). The control device 2 controls the braking force by the electric motor 6 and can adjust the amount of clearance which is the gap between the brake rotor 3 and the friction member 4.

  As shown in FIG. 2, a vehicle equipped with this electric brake device includes a vehicle speed detection unit 9 that detects a vehicle speed, that is, a vehicle speed V, an accelerator pedal operation detection unit 10, and a brake operation amount detection unit 11. For example, a vehicle speed sensor is applied as the vehicle speed detection unit 9. An accelerator pedal operation detection unit 10 as an accelerator operation amount detection unit detects an accelerator pedal operation amount (accelerator operation amount) of an accelerator pedal 12 which is an accelerator operation means. The brake operation amount detection unit 11 detects a brake operation amount of the brake pedal 13 which is a brake operation unit.

  The control device 2 includes a monitoring unit 14 and a clearance changing unit 15. The monitoring means 14 constantly detects the vehicle speed detected by the vehicle speed detection unit 9 and the accelerator pedal operation amount detected by the accelerator pedal operation detection unit 10 when the brake operation amount is not detected by the brake operation amount detection unit 11. Monitor. When the brake operation amount detection unit 11 detects the brake operation amount, the monitoring unit 14 does not monitor the vehicle speed and the accelerator pedal operation amount, and does not determine the target clearance by the clearance determination unit described later.

  The clearance changing unit 15 includes a target clearance determining unit 16 and a clearance amount adjusting unit 17. The target clearance determination unit 16 includes a clearance determination unit 16 a and a storage unit 16 b that stores determination criteria such as a threshold described later. The clearance determination unit 16a determines a target clearance that is a target value of the clearance amount.

  The clearance determination unit 16a in this embodiment expands the target clearance from the proximity state to the enlargement state when all the following set conditions (1) and (2) are simultaneously satisfied. The close state is a state in which the target clearance is narrowed in preparation for braking, and is, for example, a narrow target clearance in which the drag torque becomes weak to an acceptable degree. The enlargement state is a state in which the target clearance is made larger than the proximity state.

Condition (1): accelerator pedal operation amount A that is monitored by the monitoring unit 14 exceeds the threshold value A _H.
Condition (2): The vehicle speed V monitored by the monitoring means 14 exceeds the threshold value V _H.
The threshold value A _H and the threshold value V _H are stored in the storage unit 16b, read out as needed by the clearance determining unit 16a, and used for determination in the clearance determining unit 16a. Specific numerical values of the threshold A _H and the threshold V _H are set as follows.

Threshold value A _H : For example, the threshold value A _H is determined by reverse calculation from torque required to obtain acceleration (eg, 0.2 _G ) required at re-acceleration after signal stop.
Threshold value V _H : For example, 15 km / h or the like, which is faster than the traveling speed in such a situation, is set as the threshold value V _H so that the clearance does not change many times when moving in a garage or in a parking lot.

  When both of the above conditions (1) and (2) are satisfied, the clearance determination unit 16a determines that the driver of this vehicle has a clear intention to accelerate, and makes the target clearance an enlarged state, and the clearance amount adjustment unit Deliver to 17

  The clearance amount adjustment unit 17 performs control to match the target clearance determined by the clearance determination unit 16a. Specifically, the clearance adjustment section 17 converts the current command into a voltage value according to the determined target clearance, and finally causes the current to flow to the electric motor 6 (FIG. 1). As a result, the actual clearance amount is adjusted to the "open" state. This can improve the fuel efficiency of the vehicle.

Since the clearance amount is in the "open" state, it is subsequently checked whether the target clearance is in the close state, that is, whether the actual clearance amount is in the "closed" state. Specifically, the clearance determination unit 16 a reduces the target clearance to the close state when the accelerator pedal operation amount A monitored by the monitoring unit 14 falls below the threshold value A _L. The threshold A _L is stored in the storage unit 16b, it is read out at any time in the clearance determination unit 16a is subjected to the determination in the clearance determination unit 16a.

The specific numerical value of the threshold value A _L is, for example, back-calculated from the torque required to maintain the urban area cruising speed of 20 km / h to 30 km / h. When the accelerator pedal operation amount is smaller than the torque required for cruise, the driver can determine that there is no intention of cruise and prepares for deceleration, so the threshold value A _L is set as described above.

Also, the threshold A _L is sufficiently smaller than the threshold A _H used when the amount of clearance is adjusted to the “open” state. The difference between the threshold value A _H and the threshold value A _L often appears during vehicle cruise, and the fineness of the accelerator operation amount for finely adjusting the vehicle speed while securing the accelerator operation amount so that the vehicle speed does not decrease too much The target clearance is a relatively large difference which can prevent hunting, in which the close state and the expansion state are switched many times in a short time, which is determined by the result of a test or simulation. Since the difference between the threshold A _H and the threshold A _L is thus increased, the clearance adjustment is not performed when the accelerator pedal is operated at the time of cruising the vehicle, and the accelerator pedal operation amount is reduced as the inertia travel or braking intention becomes clear. Only when you do, reduce the amount of clearance.

FIG. 3 is a view showing an example of transition of an accelerator pedal operation amount and a vehicle speed in a vehicle equipped with this electric brake device. Hereinafter, description will be made with reference to FIGS. 1 and 2 as appropriate. It is assumed that the vehicle starts acceleration from a stop state. At this time, the electric brake device maintains the proximity state in which the clearance amount is reduced in preparation for braking. When a certain elapsed time has elapsed from the stop state, the accelerator pedal operation amount A exceeds the threshold A _H , but the vehicle speed V does not exceed the threshold V _H , so the close state is maintained.

Next, if it is determined by the clearance determination unit 16a that the accelerator pedal operation amount A exceeds the threshold A _H and the vehicle speed V exceeds the threshold V _H , the target clearance is set to the enlarged state. Thereafter, when the accelerator pedal operation amount A falls below the threshold value A _L , the target clearance is reduced to the close state. By reducing the target clearance to the close state, it is possible to prepare for braking. As a result, the sensitivity performance can be improved.

After the close state, as a reference example, when the brake pedal 13 is operated, a braking force corresponding to this brake operation amount is generated.
In the example of FIG. 4, since the clearance determination unit 16a does not simultaneously satisfy the condition that the accelerator pedal operation amount A exceeds the threshold A _H and the condition that the vehicle speed V exceeds the threshold V _H , the transition from the stop state to the proximity state remains Do.

  FIG. 5 is a flowchart of the determination of the clearance opening at the time of the clearance approach in the electric brake device. The target clearance determination unit 16 executes the process of FIG. Note that although the flowchart of FIG. 5 is a flow having processing termination as “start” and “end” for convenience of illustration, in an actual program, it is always performed after the power is turned on, and, for example, this flow is executed The calculation of the CPU of the control device 2 is performed once per cycle (the same applies to FIG. 6 described later).

It is assumed that the vehicle starts acceleration from a stop state. After the start of this process, the clearance determination unit 16a determines whether the accelerator operation amount A exceeds the threshold A _H (step a1) and the vehicle speed V exceeds the threshold V _H (step a2). When one of the conditions is not satisfied, the clearance determination unit 16a maintains the target clearance in the close state (step a3). Thereafter, the process proceeds to step a5.

  When both of the above conditions are satisfied (step a1: yes, step a2: yes), the clearance determination unit 16a changes the target clearance to the enlarged state (step a4). Thereafter, the process proceeds to step a5. In step a5, the clearance determination unit 16a transmits the determined target clearance to the clearance amount adjustment unit 17. Thereafter, the process ends.

FIG. 6 is a flow chart for determining the closing of the clearance when the clearance is enlarged in this electric brake device. After the start of this process, the clearance determination unit 16a determines whether the accelerator pedal operation amount A falls below the threshold value A _L (step b1). If it is determined that the accelerator pedal operation amount A does not fall below the threshold value A _L (step b1: no), the clearance determination unit 16a maintains the target clearance in the expanded state (step b2). Thereafter, the process proceeds to step b4.

When it is determined in step b1 that the accelerator pedal operation amount A has fallen below the threshold value A _L (step b1: yes), the clearance determination unit 16a changes the target clearance to the close state (step b3). Thereafter, the process proceeds to step b4. In step b4, the clearance determination unit 16a transmits the determined target clearance to the clearance amount adjustment unit 17. Thereafter, the process ends.

  In this embodiment, in the case of city driving, threshold values are set in consideration. However, a negative factor (superheat due to friction, fuel efficiency deterioration) in the clearance close state is an acceptable level in city driving, and at high speed cruising If there is a problem, each threshold may be raised and the control according to the embodiment may be performed only at high speed cruise.

  As a result of the above, the set target clearance is transmitted to the clearance amount adjustment unit 17. As described above, the target clearance determined up to this point is the clearance when the brake pedal 13 is not operated. Therefore, when the brake pedal 13 is operated, the brake operation amount is input to the clearance amount adjustment unit 17 from the brake operation amount detection unit 11, and the clearance amount adjustment unit is brought into contact or the like according to the brake operation amount. 17 implements control. When the brake pedal 13 is not operated, control is performed such that the actual clearance amount matches the target clearance.

  In the above flowchart, in the flowchart for determining the clearance opening when the clearance approaches in FIG. 5, when the clearance opening condition is not met, the target clearance is maintained in the proximity state (step a3) or the clearance enlargement in FIG. In the flowchart for determining the closing of the clearance, when the clearance closing conditions are not met, the target clearance is maintained in the expanded state (step b2), but in the present embodiment, it is specified that the control content is not changed This does not mean that changes due to control outside the scope of the present embodiment are not permitted.

Operation and Effect The monitoring unit 14 monitors the vehicle speed detected by the vehicle speed detection unit 9 and the accelerator operation amount detected by the accelerator pedal operation detection unit 10 when the brake is not operated. The clearance determination unit 16a determines the target clearance to be in the enlarged state when both of the monitored vehicle speed and the accelerator operation amount satisfy the set conditions. When there is a clear acceleration intention and during the subsequent cruise, there should be input of a certain amount or more of the accelerator operation while increasing or decreasing the vehicle speed by operating the accelerator pedal 12 strongly.

  If such a feature can be seen from the monitored vehicle speed or accelerator operation amount when the brake is not operated, the clearance amount is changed according to the determined target clearance. When the vehicle speed increases, road noise that increases the noise level around the vehicle makes it difficult to notice noise associated with the change in the amount of clearance even if the amount of clearance is changed. Even when the accelerator pedal operation amount exceeds a certain level, noise caused by the change in the clearance amount is hardly noticed even if the clearance amount is changed due to the noise of the engine or motor generated by the acceleration of the vehicle. Therefore, when the brake pedal 13 is not operated, the amount of clearance can be adjusted without giving a sense of discomfort to the driver.

Another embodiment will be described.
In the following description, the portions corresponding to the items described in the preceding embodiments are given the same reference numerals, and the redundant description will be omitted. When only a part of the configuration is described, the other parts of the configuration are the same as those described in the preceding embodiment unless otherwise stated. The same function and effect can be obtained from the same configuration. Not only the combination of the portions specifically described in the embodiments but also the embodiments may be partially combined if any problem does not occur in the combination.

  The above has determined the control flow to be optimal on a flat road or a gentle slope. However, in consideration of the situation in the uphill or downhill where the slope is steep, the amount of clearance should be changed even if the previously set conditions (which satisfy both the conditions (1) and (2)) are not satisfied. There is a case.

For example, as shown in FIG. 7, even if the monitored accelerator pedal operation amount A greatly exceeds the threshold value A _H and the vehicle speed V monitored does not exceed the threshold value V _H even if the state is maintained On a slope, the target clearance should be expanded to reduce drag torque as much as possible. Therefore the threshold A _VH having a value greater than the threshold value A _H, when the accelerator pedal operation amount A exceeds the threshold value A _VH, regardless of the value of the vehicle speed V, the may be a target clearance as expanded state. The threshold value _AVH is stored in the storage means, read out as needed by the clearance determination unit 16a, and provided for determination.

Further, as shown in FIG. 8, on a steep downhill where acceleration continues even if the amount of accelerator operation A falls below the threshold A _L , the cruising speed in the city is maintained without accelerator operation. It becomes. In this case, there is a concern that the brake may overheat due to dragging. Therefore, if the vehicle speed V exceeds the threshold V _VH even if the accelerator pedal operation amount A is lower than the threshold A _L , the target clearance is set to the enlarged state, and the threshold V _VH is set larger than the threshold V _H. You may maintain it. The threshold value V _{VH is} also stored in the storage means 16 b, read out as needed by the clearance determination part 16 a, and provided for determination.

FIG. 9 is a flowchart for determining the opening of the clearance of the electric brake device.
After the start, the monitoring means 14 monitors the accelerator pedal operation amount A and the vehicle speed V respectively (step c1). Clearance determination unit 16a, when the accelerator pedal operation amount A exceeds the threshold value _{A VH} (Step c2: yes), and the target clearance enlarged state (step c4). The clearance determination unit 16a enlarges the target clearance when the vehicle speed V exceeds the threshold V _VH (step c3: yes), even if the accelerator pedal operation amount A does not exceed the threshold A _VH (step c2: no). Proceed to step c4. Thereafter, the process proceeds to step c6.

If the vehicle speed V does not exceed the threshold value V _VH (step c3: no), the clearance determination unit 16a brings the target clearance close to each other (step c5). Thereafter, in step c6, the clearance determination unit 16a transmits the determined target clearance to the clearance amount adjustment unit 17. Thereafter, the process ends.

  As mentioned above, although the form for implementing this invention was demonstrated based on embodiment, embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is indicated not by the above description but by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

2 ... Control device 3 ... Brake rotor (rotary member)
4 ... friction member 5 ... friction member operation means 6 ... electric motor 9 ... vehicle speed detection unit 10 ... accelerator pedal operation detection unit (acceleration operation amount detection unit)
11 ... brake operation amount detection unit 14 ... monitoring unit 15 ... clearance changing unit 16 ... target clearance determination unit 16 a ... clearance determination unit 16 b ... storage unit 17 ... clearance amount adjustment unit

Claims (6)

Rotating member, friction member brought into contact with the rotating member, friction member operating means for bringing the friction member into contact with the rotating member to generate a braking force, electric motor for driving the friction member operating means, electric motor In an electric brake device, comprising: a control device capable of adjusting a clearance amount which is a gap between the rotating member and the friction member by controlling a motor;
The vehicle equipped with this electric brake system is
A vehicle speed detection unit that detects a vehicle speed;
An accelerator operation amount detection unit that detects an accelerator operation amount of the accelerator operation means;
A brake operation amount detection unit that detects a brake operation amount of the brake operation means;
The controller is
The vehicle speed detected by the vehicle speed detection unit and the accelerator operation amount detected by the accelerator operation amount detection unit are monitored when the brake operation amount of the brake operation unit is not detected by the brake operation amount detection unit. Monitoring means,
And a clearance changing means for changing the clearance amount when either or both of the vehicle speed and the accelerator operation amount monitored by the monitoring means satisfy the set conditions. . In the electric brake device according to claim 1,
The clearance changing means is
A target clearance determination unit that determines a target clearance that is a target value of the clearance amount;
And a clearance amount adjustment unit for adjusting an actual clearance amount to match the target clearance determined by the target clearance determination unit. Expanded in the electric brake apparatus according to claim 2, wherein the target clearance determination unit, when the accelerator operation amount monitored by said monitoring means exceeds a threshold value A _H, than proximity to the defined target clearance The electric brake device which has a clearance determination part made into the enlarged state made to be made. 4. The electric brake system according to claim 3, wherein the target clearance determining unit reduces the target clearance more than a predetermined enlargement state when the accelerator operation amount monitored by the monitoring means falls below a threshold A _L. The electric brake device which has a clearance determination part made into the close state to which it was made. 5. The electric brake system according to claim 4, wherein the target clearance determination unit uses a threshold A _H used when the target clearance is expanded from the proximity state, and the target clearance from the enlargement state to the proximity state. The electric brake device, wherein a difference is provided to the threshold value A _L used when reducing to make the time for maintaining the enlargement state longer than the time for maintaining the proximity state. The electric brake apparatus according to any one of claims 2 to 5, wherein the target clearance determination unit is greater than the vehicle speed threshold V _H is monitored by the monitoring unit, and the accelerator operation to be monitored when the amount exceeds the threshold value a _H, the electric brake apparatus having a clearance decision unit to expand state of being expanded than proximity defined the target clearance.

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