WO2017077941A1 - Brake device - Google Patents

Abstract

Provided is a brake device which is a two-piston type brake device and which reduces drag torque and delays the timing for replacing a friction-pad. The brake device is provided with the following: a brake rotor (3); a friction pad (4) which includes a plurality of pads (4a, 4b); two actuators (2-1, 2-2) which each include a piston (18), in which each piston (18) of the two actuators (2-1, 2-2) corresponds to a different pad from among the plurality of pads (4a, 4b), and which performs driving, using the pistons (18, 18), to cause the friction pad (4) to make contact with and separate from the brake rotor (3); and a control device (5) that controls the two actuators (2-1, 2-2). The control device (5) estimates the wear amount of each of the pads (4a, 4b) which correspond to the pistons (18) of the two actuators (2-1, 2-2), and in accordance with an applied braking command, independently controls each of the two actuators (2-1, 2-2) in accordance with the estimated wear amount of each of the pads (4a, 4b).

Description

Brake device Related applications

This application claims the priority of Japanese Patent Application No. 2015-215406 filed on November 2, 2015 and Japanese Patent Application No. 2016-002442 filed on January 8, 2016, which is incorporated herein by reference in its entirety. Quote as part.

The present invention relates to a two-piston type brake device, and more particularly to a brake device capable of suppressing uneven wear of the friction pad and delaying the replacement time of the friction pad.

An electric brake actuator using a motor and a linear motion mechanism has been proposed (Patent Document 1). In this electric brake actuator, one linear motion mechanism is operated by one motor. In the case of a brake that requires a large load on the front wheels when exerting a braking force in a vehicle, a two-piston type caliper is commercially available as a conventional hydraulic brake in order to apply a load uniformly to the friction pad.

Japanese Patent No. 3166401

When a large load is required as in the front wheels of the vehicle when exerting braking force, if the friction pad is pressed with a single piston (linear motion mechanism), the surface pressure of this friction pad becomes very high, and the fade phenomenon occurs. Or promote the wear of the friction pad.

On the other hand, in the actuator that drives the two pistons 80 and 80 with one control system as in the hydraulic brake shown in FIG. 23, the loads acting on the two pistons 80 and 80 are the same. As shown in FIG. 24, when the two pistons 80 and 80 are pressed with the same load, the friction pad 82 (pad portion on the upstream side in the disk rotation direction) into which the brake disk 81 enters is located downstream in the disk rotation direction. This causes uneven wear that is more worn than the friction pad. As the uneven wear of the friction pad 82 progresses, drag torque increases or early replacement of the friction pad 82 becomes necessary.

An object of the present invention is to provide a brake device capable of reducing drag torque and delaying the replacement time of a friction pad in a two-piston type brake device.

Hereinafter, in order to facilitate understanding, description will be made with reference to the reference numerals of the embodiments.

The brake device according to one configuration of the present invention includes a brake rotor 3 and
A friction pad 4 including a plurality of pad portions 4a and 4b, the friction pad 4 contacting the brake rotor 3 to generate a braking force;
Two actuators 2-1 and 2-2 (2, 2) including pistons 18 and 18 respectively, and each piston 18 of the two actuators 2-1 and 2-2 is connected to the plurality of pad portions 4a and 4b. Two actuators 2-1 and 2-2 that respectively correspond to different pad portions and drive the friction pad 4 to contact and separate from the brake rotor 3 by the pistons 18 and 18;
A control device 5 for controlling the two actuators 2-1, 2-2,
Pad portion wear amount estimating means 45 for estimating the wear amount of the pad portions 4a, 4a and 4b, 4b corresponding to the pistons 18 of the two actuators 2-1, 2-2,
The two actuators 2-1 and 2-2 are individually set according to the wear amount of the pad portions 4a, 4a and 4b, 4b estimated by the pad portion wear amount estimating means 45 in accordance with a given brake command. And a control device having an individual control unit 44 to be controlled.

Note that “individually controlled” here means that the loads of the two actuators 2-1 and 2-2 can be controlled to different values, and the load of one actuator 2 is determined. Including the case where the load of one actuator 2 is inevitably determined. Of course, “individually controlled” includes controlling the loads of the two actuators 2-1 and 2-2 to the same value.

In addition, the “amount of wear of the pad portion” is a total value of the amount of wear of the pad portion. That is, since the brake rotor is sandwiched between the friction pads from both sides, the sum of the wear amounts of the pad portions on both sides corresponds to the wear amount of the pad portions.

According to this configuration, the pad wear amount estimation means 45 estimates the combined wear amount of the pad portions 4a, 4a and 4b, 4b corresponding to the two pistons 18 and 18 in the friction pad 4, respectively. The estimated amount of wear may be, for example, at the time of starting to turn on the ignition of the vehicle, or may be at any time or periodically during vehicle operation.

The individual control unit 44 individually controls the two actuators 2 and 2 according to the estimated total wear amount of the pad portions 4a and 4a and the estimated total wear amount of the pad portions 4b and 4b. For example, when there is a difference between the estimated total wear amount of the pad portions 4a and 4a and the estimated total wear amount of the pad portions 4b and 4b, the individual control unit 44 loads the actuator 2 with less progress of wear. Is controlled to be larger than the load of the other actuator 2. In this way, by controlling the two actuators 2 and 2 individually according to the total wear amount of the pad portions 4a and 4a and the total wear amount of the pad portions 4b and 4b, the progress of uneven wear of the friction pad 4 can be promoted. Can be prevented. Thereby, drag torque can be reduced and the replacement time of the friction pad 4 can be delayed.

The two actuators 2 and 2 may have fluid pressure type drive units 58 and 58 for driving the pistons 50 and 50, respectively, using fluid as a medium. In this case, it is possible to prevent the partial wear of the friction pad 4 from progressing by individually driving the pistons 50, 50 by the fluid pressure type drive units 58, 58.

The two actuators 2 and 2 may each include an electric motor 11 and a linear motion mechanism 12 that converts the rotational motion of the electric motor 11 into the linear motion of each piston 18. In this way, in the 2-piston type electric actuator 2, it is possible to prevent the friction pad 4 from progressing unevenly.

The pad portion wear amount estimating means 45 has a pad portion remaining amount detecting portion 48 for detecting the remaining amount of the pad portions 4a, 4a and 4b, 4b corresponding to the pistons 18, 18, respectively.
The individual control unit 44 determines the second control unit according to the difference in the remaining amount of the pad portions 4a, 4a and 4b, 4b corresponding to the pistons 18 and 18 detected by the pad portion remaining amount detecting unit 48, respectively. A load correction unit 44a that corrects a load generated in the two actuators 2-1 and 2-2 may be provided.

“The remaining amount of the pad portion” is the total value of the remaining amount of the pad portion, that is, the total remaining amount. That is, since the brake rotor is sandwiched between the friction pads from both sides, the sum of the remaining amounts of the pad portions on both sides corresponds to the remaining amount of the pad portions.

According to this configuration, each pad portion remaining amount detecting unit 48 determines, for example, the remaining amount of the pad portions 4a and 4a and the remaining amount of the pad portions 4b and 4b corresponding to each piston 18 at the time of starting the vehicle or driving the vehicle. Detect each. When a predetermined difference occurs between the remaining amount of the pad portions 4a and 4a and the remaining amount of the pad portions 4b and 4b, the load correction unit 44a, for example, the remaining amount of the pad portions 4a and 4a and the pad Among the remaining amounts of the portions 4b and 4b, the load generated in one actuator 2 corresponding to the pad portion with a large remaining amount is corrected to be larger than the load generated in the other actuator 2. By correcting the load generated by each actuator 2 in this way, it is possible to prevent the uneven wear of the friction pad 4 from progressing.
The defined difference is determined by the results of tests, simulations, and the like.

The individual control units 44, 44 have the same amount of protrusion of the pistons 18, 18 of the two actuators 2-1, 2-2, and the two actuators 2-1, 2-2 respectively. The two actuators 2-1 and 2-2 may be controlled so that the total load to be generated matches the required load on the brake device. In this case, it is possible to provide a difference in the load generated by each of the actuators 2-1 and 2-2 while making the projecting amounts of the two pistons 18 and 18 the same. Progress can be prevented.

Any combination of at least two configurations disclosed in the claims and / or the specification and / or drawings is included in the present invention. In particular, any combination of two or more of each claim in the claims is included in the present invention.

The present invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying drawings. However, the embodiments and drawings are for illustration and description only and should not be used to define the scope of the present invention. The scope of the invention is defined by the appended claims. In the accompanying drawings, the same reference numerals in a plurality of drawings indicate the same or corresponding parts.
1 is a front view of a brake device according to a first embodiment of the present invention. It is a side view from the paper left side of the brake device of FIG. It is a side view from the paper surface right side of the brake device of FIG. It is a top view which shows a part of brake device of FIG. It is the VV line end view of FIG. It is the VI-VI sectional view taken on the line of FIG. It is a block diagram of the control system of the brake device of FIG. It is a block diagram which shows the detailed structure of the control apparatus of the brake device of FIG. It is a figure which shows the example of the correlation of the motor rotation angle according to the grade of pad wear, and a braking force estimated value in the brake device of FIG. It is a figure which shows the correlation of a motor rotation angle used for detection of the pad wear amount of the brake device of FIG. 1, and a braking force estimated value. In the brake device of FIG. 1, it is a figure which shows the correlation of a motor rotation angle and a brake force estimated value used in order to estimate pad part abrasion loss based on the change rate of a motor rotation angle at the time of the change of a brake force estimated value. is there. In the brake device of FIG. 1, the correlation between the second-order differential between the motor rotation angle and the brake force estimation value, which is used to estimate the pad wear amount based on the nonlinearity of the correlation between the brake force estimation value and the motor rotation angle. FIG. It is a flowchart which shows the process which controls each actuator of the brake device of FIG. It is a flowchart which shows the process which controls each actuator of the brake device which concerns on 2nd Embodiment of this invention. It is sectional drawing of the brake device which concerns on 3rd Embodiment of this invention. It is a block diagram of the control system of the brake device of FIG. It is a block diagram which shows the detailed structure of the control apparatus of the brake device which concerns on a 1st application example. It is a flowchart which shows the process which controls each actuator of the brake device of FIG. It is a figure which shows the example of the load command after correction | amendment to each actuator of FIG. It is a figure which shows the example of the load command after correction | amendment to each actuator of the brake device which concerns on a 2nd application example. It is a figure which shows the example of the load command after correction | amendment to each actuator in the brake device which concerns on a 3rd application example. It is a block diagram of the control system of the brake device which concerns on a 4th application example. It is sectional drawing of the hydraulic brake of a prior art example. It is a top view which shows the partial wear state of the friction pad of the brake device of a prior art example.

A brake device according to a first embodiment of the present invention will be described with reference to FIGS. This brake device is mounted on a vehicle. FIG. 1 is a front view of the brake device, and FIGS. 2 and 3 are left and right side views of the brake device of FIG. As shown in FIG. 3, this brake device is an electric brake device. As shown in FIG. 1, the brake device includes a caliper 1, first and second actuators 2-1 and 2-2 (FIG. 3), a brake rotor 3, and friction pads 4A and 4B (FIG. 4). And a control device 5 (FIG. 1). In the present specification, when the actuator 2 is simply referred to, it may correspond to both the first actuator 2-1 and the second actuator 2-2.

As shown in FIGS. 2 and 3, two actuators (first and second actuators) 2-1 and 2-2 are arranged in parallel in a single caliper 1 at a predetermined interval. As shown in FIG. 4, these actuators 2 and 2 drive the friction pad (an inboard side friction pad to be described later) 4B (FIG. 5) to contact and separate from the brake rotor 3 (FIG. 4). The predetermined interval is appropriately determined according to the dimensions of the friction pad 4 and the first and second actuators 2-1, 2-2.

FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. Therefore, hereinafter, the first actuator 2-1 will be described, but this description also applies to the second actuator 2-2. As shown in FIG. 6, the caliper 1 is provided for each brake device in the vehicle so as to surround the outer peripheral side portion of the brake rotor 3. A claw portion 6 is provided at an end portion of the caliper 1 on the outboard side. An outboard side friction pad 4A located on the outboard side is supported by the claw portion 6. The outboard side friction pad 4 </ b> A faces the side surface of the brake rotor 3 on the outboard side in the axial direction. In this specification, in the state where this brake device is mounted on a vehicle, the vehicle width direction outer side of the vehicle is referred to as an outboard side, and the vehicle width direction center side of the vehicle is referred to as an inboard side.

In the caliper 1, the inboard side friction pad 4 </ b> B located on the inboard side is supported at the outboard side end of the actuator 2. The inboard friction pad 4B faces the inboard side surface of the brake rotor 3 in the axial direction. The actuator 2 drives the inboard side friction pad 4 </ b> B to abut against and separate from the brake rotor 3. In the present specification, when it can correspond to both the outboard side friction pad 4A and the inboard side friction pad 4B, it is simply referred to as the friction pad 4.

The mount 7 is supported by a knuckle (not shown) in the vehicle. As shown in FIG. 3, pin support pieces 8 and 8 are provided at both ends in the longitudinal direction of the mount 7. Slide pins 9 and 9 extending in parallel with each other in the axial direction are provided at the ends of the pin support pieces 8 and 8, respectively. The caliper 1 is supported by these slide pins 9 and 9 so as to be slidable in the axial direction.

As shown in FIG. 6, during braking, the inboard friction pad 4 </ b> B comes into contact with the brake rotor 3 by driving an actuator 2 described later, and presses the brake rotor 3 in the axial direction. The caliper 1 slides to the inboard side by the reaction force of the pressing force. As a result, the outboard friction pad 4 </ b> A supported by the claw portion 6 of the caliper 1 contacts the brake rotor 3. The outboard side / inboard side friction pads 4 </ b> A and 4 </ b> B strongly hold the brake rotor 3 from both sides in the axial direction, so that a braking force is applied to the brake rotor 3.

As shown in FIG. 3, the first and second actuators 2-1 and 2-2 include housings 10 and 10, electric motors 11 and 11, and first and second linear motion mechanisms 12-1, respectively. , 12-2 (FIG. 6) and speed reduction mechanisms 13, 13. Two cylindrical housings 10 are fixed to the caliper 1. The electric motors 11 are supported by the housings 10 and 10 respectively. As shown in FIG. 6, a linear motion mechanism 12 is incorporated in the housing 10, and the linear motion mechanism 12 applies a braking force to the brake rotor 3 according to the output of the electric motor 11 (FIG. 3). In the present specification, the simple term of the linear motion mechanism 12 may correspond to both the first linear motion mechanism 12-1 and the second linear motion mechanism 12-2.

The linear motion mechanism 12 is a mechanism that converts the rotational motion output from the speed reduction mechanism 13 into a linear motion and causes the friction pad 4 to abut against and separate from the brake rotor 3. The linear motion mechanism 12 includes a rotary shaft 14 that is rotationally driven by the electric motor 11 (FIG. 3), a conversion mechanism portion 15 that converts the rotational motion of the rotary shaft 14 into linear motion, and restraint portions 16 and 17. Have. The conversion mechanism portion 15 includes a linear motion portion 18 that is a piston, a support member 19, a backup plate 20 that is an annular thrust plate, a thrust bearing 21, a rolling bearing 22, a carrier 23, a first and a second. Slide bearings 24 and 25 and a plurality of planetary rollers 26.

A cylindrical linear motion portion 18 is supported on the inner peripheral surface of the housing 10 so as to be prevented from rotating and movable in the axial direction. On the inner peripheral surface of the linear motion portion 18, a spiral protrusion is provided that protrudes a predetermined distance radially inward and is formed in a spiral shape. A plurality of planetary rollers 26 are engaged with the spiral protrusions.

The support member 19 is provided on one end side in the axial direction of the linear motion portion 18 in the housing 10. The support member 19 has a boss portion and a flange portion extending radially outward from the boss portion. A plurality of rolling bearings 22 are fitted in the boss portion, and the rotary shaft 14 is fitted to the inner ring inner diameter surface of the rolling bearings 22. The rotary shaft 14 is rotatably supported by the support member 19 via a plurality of rolling bearings 22.

A carrier 23 that can rotate around the rotation shaft 14 is provided on the inner periphery of the linear motion portion 18. The carrier 23 has a pair of disks that are arranged to face each other in the axial direction. Of these disks, the disk close to the support member 19 is referred to as an inner disk, and the other disk is referred to as an outer disk. A plurality of pillar members are provided on a side surface of the outer side disk facing the inner side disk so as to protrude in an axial direction (inboard side) from an outer peripheral edge portion on the side surface. The outer side disc and the inner side disc are integrally provided by the plurality of column members.

The inner disk is rotatably supported on the rotary shaft 14 by a first slide bearing 24 fitted between the inner disc and the rotary shaft 14. A shaft insertion hole is formed in the center of the outer side disk, and a second plain bearing 25 is fitted in this shaft insertion hole. The outer disk is rotatably supported on the rotary shaft 14 by the second slide bearing 25. The restraining portions 16 and 17 for restraining the axial positions of the rotating shaft 14 and the carrier 23 with respect to the support member 19 are provided at both ends in the axial direction of the rotating shaft 14.

The carrier 23 is provided with a plurality of roller shafts 27 at intervals in the circumferential direction. Both end portions in the axial direction of each roller shaft 27 are supported across the inner side disk and the outer side disk. Both discs have a plurality of shaft insertion holes. Each shaft insertion hole is composed of a long hole extending a predetermined distance in the radial direction. Both axial ends of each roller shaft 27 are inserted into the respective shaft insertion holes, and these roller shafts 27 are supported so as to be movable in the radial direction within the range of the respective shaft insertion holes. An elastic ring 28 that urges the roller shafts 27 inward in the radial direction is stretched between both axial ends of the plurality of roller shafts 27.

The planetary roller 26 is rotatably supported on each roller shaft 27. On the outer peripheral surface of each planetary roller 26, a circumferential groove or a spiral groove that meshes with the spiral protrusion of the linear motion portion 18 is formed. Each planetary roller 26 is interposed between the outer peripheral surface of the rotating shaft 14 and the inner peripheral surface of the linear motion portion 18. Each planetary roller 26 is pressed against the outer peripheral surface of the rotating shaft 14 by the urging force of the elastic ring 28. As the rotating shaft 14 rotates, each planetary roller 26 that contacts the outer peripheral surface of the rotating shaft 14 rotates due to contact friction.

The speed reduction mechanism 13 is a mechanism for decelerating and transmitting the rotation of the electric motor 11 (FIG. 3) to an output gear 29 fixed to the rotary shaft 14. As shown in FIG. 3, the speed reduction mechanism 13 includes a plurality of gear trains. In this embodiment, the speed reduction mechanism 13 can reduce the rotation of the input gear 30 attached to the rotor shaft (not shown) of the electric motor 11 by the intermediate gear 31 and transmit it to the output gear 29.

FIG. 7 is a block diagram of the control system of this brake device. The brake device control device 5 controls the two actuators 2 and 2 (first and second actuators 2-1 and 2-2), respectively. The control device 5 includes a brake force command means 32 a provided in the ECU 32 and two inverter devices 33 and 33 respectively corresponding to the two actuators 2 and 2. For example, an electric control unit that controls the entire vehicle is applied as the ECU 32 that is a higher-level control unit of each inverter device 33. The brake force command means 32a of the ECU 32 generates and outputs a target brake force command value for each wheel according to the output of the brake sensor 34a that detects the amount of operation of the brake pedal, which is the brake operation means 34.

As shown in FIG. 8, each inverter device 33 includes a braking force estimation means 35, a power circuit unit 36 provided for each electric motor 11, a motor control unit 37 that controls the power circuit unit 36, Warning signal output means 38 and current detection means 39 are provided.

The brake force estimation means 35 is a means for obtaining an estimated value of the brake force that presses the friction pad 4 (FIG. 4) against the brake rotor 3 (FIG. 4). The brake force estimating means 35 obtains an estimated value of the corresponding brake force by calculation from the output of the brake sensor 34a and the motor current detected by the current detecting means 39. The relationship between the output of the brake sensor 34a, the motor current, and the estimated value of the braking force is appropriately determined by, for example, the result of one or both of the test and simulation, and is recorded in the recording means 40 so as to be rewritable. .

The brake force estimating means 35 may further include a load sensor (not shown) for detecting the axial load of the linear motion mechanism 12 (FIG. 6). In this case, the control device 5 advances the linear motion portion 18 (FIG. 6) from the position away from the brake rotor 3 (FIG. 6) to the outboard side, and uses the minimum detection value that can be detected by this load sensor. Get a certain braking force.

The brake force, which is a detection value detected by the load sensor, gradually increases in accordance with the operation amount that further depresses the brake operation means 34. By using the detection value of the load sensor, the braking force can be detected with high accuracy. Further, a torque estimating means 41 for estimating the motor torque from the motor current detected by the current detecting means 39 may be provided, and the braking force may be estimated using the torque estimated by the torque estimating means 41.

The motor control unit 37 includes a computer, a program executed by the computer, and an electronic circuit. In the present embodiment, the motor control unit 37 corrects the command value of the brake force given from the brake force command means 32a as will be described later, and converts the corrected command value into a current command represented by a voltage value. Then, this current command is given to the power circuit unit 36. The motor control unit 37 has a function of outputting information such as detection values and control values relating to the electric motor 11 to the ECU 32. The brake force estimating means 35 is also composed of a computer, a program executed by the computer, and an electronic circuit.

The power circuit unit 36 includes an inverter 36b that converts the DC power of the power source 42 into three-phase AC power used to drive the electric motor 11, and a PWM control unit 36a that controls the inverter 36b. The electric motor 11 is composed of a three-phase synchronous motor or the like. The electric motor 11 is provided with motor rotation angle detection means 43 for detecting the rotation angle of the rotor. The inverter 36b is composed of a plurality of semiconductor switching elements (not shown), and the PWM controller 36a performs pulse width modulation on the input current command and gives an on / off command to each of the semiconductor switching elements.

The motor control unit 37 has a motor drive control unit 44 as an individual control unit. The motor drive control unit 44 converts a corrected command value, which will be described later, into a current command represented by a voltage value, and gives a motor operation command value including the current command to the PWM control unit 36a. The motor drive control unit 44 obtains a motor current flowing from the inverter 36b to the electric motor 11 from the current detection means 39, and performs current feedback control on the corrected command value. The motor drive control unit 44 also obtains a motor rotation angle from the motor rotation angle detection means 43 and gives a current command to the PWM control unit 36a so that efficient motor driving according to the motor rotation angle can be performed.

Each motor drive control unit 44 has a load correction unit 44a. The load correction unit 44a of the inverter device 33 corresponding to the first actuator 2-1 (FIG. 7) has an inboard friction pad 4A (see FIG. 5) obtained by the corresponding pad portion wear amount estimation means 45 (details will be described later). 4) The remaining amount of the pad portion 4a of the pad portion 4a and the pad portion 4a of the outboard friction pad 4B (FIG. 4), and the estimation of the pad portion wear amount of the inverter device 33 corresponding to the second actuator 2-2 (FIG. 7) Depending on the difference between the combined remaining amount of the pad portion 4b of the inboard friction pad 4A (FIG. 4) and the pad portion 4b of the outboard friction pad 4B (FIG. 4) obtained by the means 45, the first actuator 2 -1 (Fig. 7) to correct the load (command value) generated. Similarly, the load correction unit 44a of the inverter device 33 corresponding to the second actuator 2-2 (FIG. 4) also corrects the load (command value) generated by the second actuator 2-2 (FIG. 7). . For example, each load correction unit 44a corresponds to the command value given from the brake force command means 32a when the corresponding pad unit 4a, 4a or 4b, 4b (FIG. 4) is not worn, and the corresponding pad unit 4a, 4a and 4b. , 4b (that is, the difference between the total remaining amount of the pad portions 4a and 4a and the total remaining amount of the pad portions 4b and 4b) and a value multiplied by a coefficient are corrected. However, the sum of the command values of the first and second actuators 2-1 and 2-2 (FIG. 7) does not change before and after the correction. In other words, the two load correction units 44a and 44a are configured so that the total load generated by the first and second actuators 2-1 and 2-2 (FIG. 7) is a required load (command) to the brake device. The first and second actuators 2-1 and 2-2 (FIG. 7) are controlled so as to coincide with each other.

Note that the total remaining amount of the pad portions 4a and 4a obtained by the pad wear amount estimating means 45 of the inverter device 33 corresponding to the first actuator 2-1 corresponds to the second actuator 2-2 via the ECU 32. It may be transmitted to the inverter device 33. Similarly, the total remaining amount of the pad portions 4b and 4b obtained by the pad wear amount estimating means 45 of the inverter device 33 corresponding to the second actuator 2-2 corresponds to the first actuator 2-1 via the ECU 32. May be transmitted to the inverter device 33. Instead, the total remaining amount of the pad portions 4a and 4a obtained by the pad wear amount estimating means 45 of the inverter device 33 corresponding to the first actuator 2-1 and the inverter device 33 corresponding to the second actuator 2-2. The ECU 32 is notified of the total remaining amount of the pad portions 4b and 4b obtained by the pad wear amount estimating means 45, and the ECU 32 uses the physical amount used by the load correction unit 44a of each inverter (for example, the total) from the total remaining amount. (Residual amount deviation or the like) may be calculated and the value may be transmitted to each inverter 33.

Each motor control unit 37 is provided with pad portion wear amount estimation means 45, recording means 40, and the like. As shown in FIGS. 4 and 5, the pad portion wear amount estimating means 45 of the inverter device 33 corresponding to the first actuator 2-1 (FIG. 7) is the first linear motion mechanism 12- in the friction pad 4. 1 (FIG. 6), the combined wear amount of the pad portions 4a and 4a is estimated. Similarly, the pad portion wear amount estimation means 45 of the inverter device 33 corresponding to the second actuator 2-2 (FIG. 7) also has a pad portion 4b corresponding to the second linear motion mechanism 12-2 (FIG. 6). The total wear amount of 4b is estimated. That is, the pad portions 4a and 4a corresponding to the first linear motion mechanism 12-1 (FIG. 6) in the first actuator 2-1 in the friction pad 4 are connected to the linear motion mechanism 12-1 (FIG. 6). The corresponding half of the friction pad 4 (the upstream portion of the brake rotor 3 in the rotational direction). Pad portions 4b and 4b corresponding to the second linear motion mechanism 12-2 (FIG. 6) in the second actuator 2-2 in the friction pad 4 correspond to the second linear motion mechanism 12 (FIG. 6). This is a substantially half portion of the friction pad 4 (portion on the downstream side in the brake rotor rotation direction).

As shown in FIG. 8, each pad wear amount estimation means 45 calculates the friction between the motor rotation angle detected by the motor rotation angle detection means 43 and the estimated brake force value obtained by the brake force estimation means 35. The pad portions 4a, 4a or 4b, 4b (FIG. 4) of the pad 4 are compared with the determined correlation between the motor rotation angle and the estimated brake force when the pad 4 is not worn, and the pad portion 4a, The total wear amount of 4a or 4b, 4b (FIG. 4) is estimated. The amount of wear is determined by subtracting the current remaining amount from the thickness of each pad portion 4a, 4a and 4b, 4b when not worn.

The warning signal output means 38 outputs a warning signal to the ECU 32 when the total wear amount of the pad portions 4a, 4a or 4b, 4b (FIG. 4) estimated by the corresponding pad portion wear amount estimation means 45 is equal to or greater than a threshold value. . The threshold value is recorded in the recording means 40 so as to be rewritable. An output means 46 such as a warning display such as a display, a warning light, or an audio output device is provided on a console panel or the like in the vehicle. When the warning signal is input from the warning signal output means 38, the ECU 32 causes the warning display or the like output means 46 to output a warning display or the like. The driver of the vehicle can recognize that the wear limit of the friction pad 4 is close by the output warning display or the like.

FIG. 9 is a diagram showing an example of the correlation between the motor rotation angle and the estimated brake force value according to the degree of pad wear in the brake device. The correlation between the motor rotation angle and the estimated braking force mainly depends on the rigidity of the caliper 1 shown in FIG. 6, the compression rigidity of the friction pad 4, and the rigidity of the actuator 2. Among these, the rigidity of the caliper 1 and the actuator 2 does not change even when the braking force is continuously generated, and remains almost a known constant magnitude. In general, the amount of wear of the brake rotor 3 is small compared to the amount of wear of the friction pad 4, and the amount of compressive deformation of the brake rotor 3 is extremely small relative to the rigidity of the entire brake. There is almost no impact on the overall stiffness.

On the other hand, the compression rigidity of the friction pad 4 is very low compared to the brake rotor 3 and the like, and the influence on the rigidity of the entire brake is great. Therefore, the rigidity of the entire brake increases as wear of the friction pad 4 progresses and the rigidity of the friction pad 4 increases.

The pad portion wear amount estimation means 45 in FIG. 8 is based on the difference between the predetermined correlation between the motor rotation angle and the brake force estimated value when not worn and the correlation between the current motor rotation angle and the brake force estimated value. Thus, the total wear amount of each pad portion 4a, 4a or 4b, 4b (FIG. 4) of the friction pad 4 can be estimated.

As shown by the solid line in FIG. 9, the friction pad 4 (FIG. 4) exhibits a strong nonlinearity with respect to the correlation between the motor rotation angle and the estimated brake force when the friction pad 4 (FIG. 6) is not worn. Specifically, when the motor rotation angle is represented by the horizontal axis and the brake estimated value is represented by the coordinate of the vertical axis, the motor rotation angle and the brake estimated value are not proportional but have a correlation of curves protruding toward the horizontal axis. As shown by the dotted line in FIG. 9, in the state where the amount of wear of the pad portion is “medium”, that is, the state where wear proceeds but before the wear limit is reached, the correlation becomes more linear than in the non-wear state. Specifically, when the motor rotation angle is represented by the horizontal axis and the brake estimated value is represented by the coordinate of the vertical axis, the motor rotation angle and the brake estimated value exhibit a correlation of curves protruding to the horizontal axis side, but compared with the non-wearing state. Close to a straight line. As shown by the one-dot chain line in FIG. 9, in the state where the wear limit of the pad portion wear amount is large, the correlation becomes more linear than in the state where the pad wear amount is “medium”. Specifically, when the motor rotation angle is represented by the horizontal axis and the brake estimated value is represented by the coordinate of the vertical axis, the motor rotation angle and the brake estimated value exhibit a correlation of curves protruding toward the horizontal axis, but are very close to a straight line. .

FIG. 10 is a diagram showing the correlation between the motor rotation angle of this brake device and the estimated brake force value, which is used for explaining an example of detecting the pad wear amount. The motor rotation angle θ necessary for exerting a constant braking force F becomes the motor rotation angle θ ′ in a state after the friction pad 4 (FIG. 6) is worn. The brake force F is estimated by the brake force estimating means 35 in FIG. The motor rotation angle θ (θ ′) is detected by the motor rotation angle detection means 43. The pad wear amount estimation means 45 is a map or the like that defines the relationship between the change amount of the motor rotation angle and the pad wear amount (that is, a map showing the relationship of the graph of FIG. 9 or FIG. From the map showing the correlation for each amount, the total wear amount of the pad portions 4a, 4a or 4b, 4b (FIG. 4) of the friction pad 4 can be accurately estimated.

FIG. 11 shows the correlation between the motor rotation angle and the brake force estimated value, which is used to estimate the pad wear amount based on the rate of change of the motor rotation angle when the brake force estimated value changes. FIG. As described above, as the pad wear progresses, the correlation between the motor rotation angle and the brake force estimated value approaches linear. Then, the motor rotation angle when the brake force estimation value changes from, for example, F1 to F2 under a condition where either one of the brake force estimation value and the motor rotation angle continues to increase or decrease more than a predetermined value. By detecting the change Δθ (Δθ ′), whether the correlation between the motor rotation angle and the brake force estimation value is non-linear or close to linear, that is, the gradient of the brake force estimation value with respect to the motor rotation angle is reduced. Can be detected. Thereby, the progress of pad wear can be determined.

In addition, when estimating the amount of wear of the pad portion, the correlation between the change rates of the motor rotation angle θ and the brake force estimated value F may be used. That is, a value of dF / dθ at a predetermined motor rotation angle θ or a value of dθ / dF at a predetermined brake force estimation value F may be used.

FIG. 12 is a diagram illustrating an example in which the amount of wear on the pad portion is estimated based on the strength of the nonlinearity of the correlation between the brake force estimated value and the motor rotation angle in this brake device. The pad portion wear amount estimating means 45 of FIG. 8 in this brake device includes a linearity determining portion 47 and a pad portion remaining amount detecting portion 48. The linearity determination unit 47 determines the strength of the linearity of the correlation between the brake force estimated value and the motor rotation angle. The pad remaining amount detection unit 48 determines each pad unit 4a of the friction pad 4 from the estimated brake force value or the motor rotation angle at which the linearity of the correlation determined by the linearity determination unit 47 is equal to or greater than a threshold value. , 4a or 4b, 4b (FIG. 4).

The linearity determination unit 47 shown in FIG. 8 obtains the change in the other change rate with respect to either the brake force estimated value or the motor rotation angle by, for example, differentiating the one with the other twice, and the correlation. The strength of linearity may be detected. At this time, in the region where the estimated brake force value is extremely low, the detection accuracy may not be stable. Therefore, a condition more than a predetermined brake force estimate value or a predetermined motor rotation angle may be separately provided. The determined brake force estimated value and the determined motor rotation angle are the minimum value of the estimated brake force value that stabilizes the detection accuracy, or the motor rotation angle that stabilizes the detection accuracy. It is determined based on the minimum angle.

FIG. 13 is a flowchart showing a process for controlling the first and second actuators 2-1 and 2-2 (FIG. 7) of the brake device. Referring to FIGS. 8 and 13, for example, when the ignition of the vehicle is turned on, this process is started, and motor control units 37 and 37 receive a brake force command value for each actuator from brake force command means 32a. Tf is acquired (step a1). Next, the pad wear amount estimation means 45 and 45 determine the combined wear amount of the pad portions 4a and 4a and the combined wear amount of the pad portions 4b and 4b (FIG. 4), respectively. The load correction units 44a and 44a calculate a difference (pad portion remaining amount deviation) ΔPt between the combined remaining amount of the pad portions 4a and 4a (FIG. 4) and the combined remaining amount of the pad portions 4b and 4b (FIG. 4) (step). a2).

Next, each load correction unit 44a has a pad portion corresponding to the command value (Tf / 2) for each actuator given from the brake force command means 32a when the corresponding pad portion 4a (or 4b) (FIG. 4) is not worn. A correction is made by adding a value obtained by multiplying the pad portion total remaining amount deviation ΔPt, which is the difference between the total remaining amount of 4a, 4a (FIG. 4) and the combined remaining amount of the pad portions 4b, 4b (FIG. 4), by a coefficient k * (see FIG. 4). Step a3). In this step a3, the load correction unit 44a, for example, is one actuator 2 (for example, the first actuator 2-1) (for example, the first actuator 2-1) having a large total remaining amount of the pad portions 4a, 4a or 4b, 4b (FIG. 4) (FIG. ) Is made larger than the load (corrected command value) generated by the other actuator 2 (for example, the second actuator 2-2) (FIG. 7). Correction is performed with a coefficient k * that is different for each actuator. However, the sum of the command values of the two actuators 2 and 2 (FIG. 7) does not change before and after the correction. Thereafter, the inverter devices 33 and 33 individually control the load of the corresponding actuators 2 (FIG. 7) according to the corresponding corrected command values (step a4). Thereafter, this process is terminated.

According to the brake device described above, each motor drive control unit 44 includes two actuators according to the estimated total wear amount of the pad portions 4a and 4a and the estimated total wear amount of the pad portions 4b and 4b. 2 and 2 are controlled individually. For example, when there is a difference between the estimated total wear amount of the pad portions 4a and 4a and the estimated total wear amount of the pad portions 4b and 4b, each motor drive control unit 44 has one of the wear progresses less. Control is performed so that the load of the actuator 2 is larger than the load of the other actuator 2. In this way, the uneven wear of the friction pad 4 progresses by individually controlling the two actuators 2 and 2 according to the total wear amount of the pad portions 4a and 4a and the total wear amount of the pad portions 4b and 4b. Can be prevented. Thereby, drag torque can be reduced and the replacement time of the friction pad 4 can be delayed.

A second embodiment of the present invention will be described.
In the following description, the same reference numerals are assigned to the portions corresponding to the matters described in the preceding forms in each embodiment, and overlapping descriptions are omitted. When only a part of the configuration is described, the other parts of the configuration are the same as those described in advance unless otherwise specified. The same effect is obtained from the same configuration. Not only the combination of the parts specifically described in each embodiment, but also the embodiments can be partially combined as long as the combination does not hinder.

FIG. 14 is a flowchart showing a process for controlling the first and second actuators 2-1 and 2-2 (FIG. 7) of the brake device. Referring to FIGS. 14 and 8, after starting the process of controlling actuator 2 (FIG. 7), motor control units 37 and 37 obtain a command value Tf of the braking force for each actuator (step b1). Next, the pad portion wear amount estimation means 45, 45 respectively calculate the average value of the remaining pad portion for each of a plurality of times for each pad portion (step b2). The plurality of times may be determined in advance, may be a plurality of times at regular intervals from an arbitrary start time, or may be a plurality of times for each operation of the brake operation unit 34.

Next, each motor drive control unit 44 determines the target angle of the corresponding electric motor 11 from the average value of the corresponding pad portion remaining amount (step b3). Further, each of the motor drive control units 44 and 44 ensures that the total estimated load of the actuator 2 (FIG. 7) corresponding to the determined target angle matches the required load (command value) for the brake device ( Step b4), the angle of each electric motor 11 of the two actuators 2 (FIG. 7) is controlled (step b5). Thereafter, this process is terminated.

According to this configuration, since the target angle of each electric motor 11 is determined from the average value of the respective remaining pad portions, even when the remaining pad portions change from moment to moment, the pad portions 4a and 4a (see FIG. The total wear amount of 4) and the total wear amount of the pad portions 4b and 4b (FIG. 4) can be estimated finely.

The two motor drive control units 44 and 44 shown in FIGS. 4 and 8 have the same amount of protrusion of the two linear motion mechanisms 12 and 12 and the total load generated by the two actuators 2 and 2 is the same as that described above. The two actuators 2 and 2 may be controlled so as to coincide with the required load on the brake device. In this case, it is possible to provide a difference in the load generated by each of the actuators 2 and 2 while making the protruding amounts of the two linear motion mechanisms 12 and 12 the same. Can be prevented.

FIG. 15 is a cross-sectional view of a brake device according to a third embodiment of the present invention, and FIG. 16 is a block diagram of a control system of the brake device. As shown in FIG. 15, the first actuator 2-1 (2) and the second actuator 2-2 (2) are fluid pressure type drive units 58 and 58 for driving the pistons 50 and 50, respectively, using fluid as a medium. It is good also as what has. The piston 50 corresponds to the linear motion portion 18 (FIG. 6) described in the first embodiment. The drive units 58 and 58 each include a hydraulic cylinder having a wheel cylinder 51 in which a first hydraulic chamber 53 and a second hydraulic chamber 54 are formed, and a corresponding piston 50. Two pistons 50 and 50 are arranged in parallel to each other in one wheel cylinder 51. The pistons 50 and 50 are configured to be movable forward and backward by a first oil passage 59-1 (59) and a second oil passage 59-2 (59) which are independent of each other.

As shown in FIG. 16, a fluid pressure type drive source 49 is provided in a vehicle on which the brake device is mounted. The drive source 49 includes a hydraulic pump 49a and a motor 49b that drives the hydraulic pump 49a. The discharge port of the hydraulic pump 49a is branched into a first oil passage 59-1 and a second oil passage 59-2. Intensified linear valves 52 and 52 are interposed in the middle of the piping of the first and second oil passages 59-1 and 59-2, respectively. The first and second oil passages 59-1 and 59-2 are connected by piping to the first and second hydraulic chambers 53 and 54 of the wheel cylinder 51, respectively.

The control device 5A changes the magnitude of the drive signal according to the output of the brake sensor 34a that detects the operation amount of the brake operation means 34. Both the pressure-increasing linear valves 52 and 52 are so-called normally closed valves whose normal state is “closed”, and when the drive signal is given from the control device 5A, the opening degree is increased in accordance with the magnitude of the drive signal. As a result, the hydraulic pressure in each of the hydraulic chambers 53 and 54 of the wheel cylinder 51 increases in accordance with the increase amount of the opening degree of the corresponding pressure increasing linear valve 52. Therefore, the friction pad 4 comes into contact with the brake rotor 3 to generate a braking force.

The first and second hydraulic pressure sensors 55 and 56 for detecting the hydraulic pressures of the hydraulic chambers 53 and 54, respectively, are provided below the respective pressure-increasing linear valves 52 and 52. The detection values of these hydraulic sensors 55 and 56 are input to the control device 5A. Further, flow meters Sb1 and Sb2 are installed on the first and second oil passages 59-1 and 59-2, respectively, and the flow rate of the fluid is detected by these flow meters Sb1 and Sb2, and these detected values are controlled. Input to the device 5A. Furthermore, stroke sensors Sa1 and Sa2 are provided in the drive units 58 and 58, respectively, and the movement amounts of the pistons 50 and 50 detected by the stroke sensors Sa1 and Sa2 are input to the control device 5A. Each individual control unit 57 of the control device 5A moves the movement amount of the pistons 50, 50 calculated from the detection values of the first and second hydraulic sensors 55, 56 and the detection values of the flow meters Sb1, Sb2 or the stroke sensors Sa1, Sa2. Based on the above, the difference between the total wear amount of the pad portions 4a and 4a and the total wear amount of the pad portions 4b and 4b is calculated, and the hydraulic pressure generated by the first and second actuators 2-1 and 2-2 is calculated. to correct. The wear amount of the pad may be detected using the horizontal axis in FIGS. 9 to 12 referred to in the description of the first embodiment as the piston movement amount. The relationship between the difference between these detected values and the difference in the amount of wear of each pad 4a, 4a is determined by the results of tests, simulations, and the like. Note that the piston movement amount may be calculated using only one of the flow meters Sb1 and Sb2 and the stroke sensors Sa1 and Sa2. In this way, the two actuators 2 and 2 are individually controlled in accordance with the difference in the pad wear amount calculated from the detected values of the hydraulic sensors 55 and 56 and the piston movement amount, thereby causing the partial wear of the friction pad 4 to progress. Can be prevented. Thereby, drag torque can be reduced and the replacement time of the friction pad 4 can be delayed.

In each embodiment, the configuration may be such that the pad wear amount estimation means and the warning display output means are omitted. In this case, the configuration of the control device can be simplified and the calculation processing load can be reduced.

As mentioned above, although the form for implementing this invention based on embodiment was demonstrated, embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

A brake device according to a first application example of the present invention will be described with reference to FIGS. 1 to 7 and FIG. 17 referred to in the first embodiment. In the following description, the same reference numerals are assigned to portions corresponding to the matters described in the first embodiment, and overlapping descriptions are omitted. When only a part of the configuration is described, the other parts of the configuration are the same as those in the first embodiment unless otherwise specified.

In the brake device of the first embodiment, the brake force command means 32a of the ECU 32 is a target brake for each wheel according to the output of the sensor 34a that changes according to the amount of operation of the brake pedal that is the brake operation means 34. The force command value is generated and output, but in this application example, a brake force (brake command) described later is generated and output.

In the first application example, the motor control unit 37 includes a motor drive control unit 44A different from that of the first embodiment. The motor drive control unit 44A also includes a load correction unit 44Aa that is different from that of the first embodiment. The load correction unit 44Aa corrects a load (command value) generated by the corresponding actuator 2 in accordance with the brake command and the rotation speed and rotation direction of the brake rotor 3 (FIG. 4). This uniformly equalizes the amount of wear of the pad portion 4a (FIG. 4) on the inlet side and the pad portion 4b (FIG. 4) on the outlet side, thereby preventing uneven wear of the friction pad 4 (FIG. 4). Because. In addition, the “pad portion on the turn-in side” refers to a pad portion located on the upstream side in the rotation direction of the brake rotor 3, and the “pad portion on the turn-out side” is located on the downstream side in the rotation direction in the brake rotor 3. Refers to the pad part to be used. In addition, “the upstream side in the rotational direction” and “the downstream side in the rotational direction” are the upstream side and the downstream side in the rotational direction of the brake rotor when the vehicle moves forward, respectively, and the vehicle moves backward when the vehicle moves backward. The upstream side and the downstream side in the rotational direction of the brake rotor at the time, and the reverse occurs when the vehicle is moving forward and backward.

Each wheel of the vehicle is provided with, for example, a wheel speed sensor 41 as detection means. The rotation speed and direction of the brake rotor 3 (FIG. 4) are detected by a wheel speed sensor 41 provided on each wheel.

FIG. 18 is a flowchart showing a process for controlling the first and second actuators 2-1 (2), 2-2 (2) (FIG. 7) of the brake device. Referring to FIGS. 17 and 18, for example, when the ignition of the vehicle is turned on, this process is started, and motor control units 37 and 37 acquire a brake command for each actuator from brake force command means 32a. (Step S1). Next, the motor drive control units 44A and 44A acquire the rotation speed and rotation direction of the brake rotor 3 (FIG. 4) from the wheel speed sensor 41 (steps S2 and S3).

Next, the load correction units 44Aa and 44Aa use the first and second actuators 2-1 and 2-2 in accordance with the acquired brake command and the rotation speed and rotation direction of the brake rotor 3 (FIG. 4). The load to be generated is corrected (step S4). For example, the load of the second actuator 2-2 corresponding to the pad portion 4b (FIG. 4) on the delivery side is changed to the load of the first actuator 2-1 corresponding to the pad portion 4a (FIG. 4) on the return side. To a value larger than However, the sum of the command values of the two actuators 2 and 2 does not change before and after the correction. Thereafter, the inverter devices 33 and 33 respectively perform load control on the corresponding actuators 2 in accordance with the corresponding corrected command values (step S5). Thereafter, this process is terminated.

FIG. 19 is a diagram illustrating an example of a load command after correction to each actuator. Hereinafter, description will be made with reference to FIG. 17 as appropriate.
In the example of FIG. 19, the two motor drive control units 44A and 44A (FIG. 17) are arranged in a region where the total sum of loads generated by the two actuators 2 and 2 (FIG. 17), that is, the total load is not more than a predetermined load. Only the load of the second actuator 2-2 (FIG. 17) corresponding to the pad portion 4b (FIG. 4) on the delivery side is controlled. Thereafter, the two motor drive control units 44A and 44A (FIG. 17) cause the load generated by both actuators 2 and 2 (FIG. 17) until the first actuator 2-1 (FIG. 17) reaches the maximum load. Increase at the same rate.

The effect will be described.
According to the brake device of the first application example described above, the two motor drive control units 44A and 44A have loads generated by the two actuators 2 and 2 in accordance with the brake command and the rotation speed and rotation direction. Are controlled individually. Thus, by controlling the two actuators 2 and 2 individually, uneven wear of the friction pad 4 can be prevented beforehand. Thereby, drag torque can be reduced and the replacement time of the friction pad 4 can be delayed.

By controlling the load of the second actuator 2-2 corresponding to the pad portion 4b on the return side with a value larger than the load of the first actuator 2-1 corresponding to the pad portion 4a on the return side. Further, the wear amount of the pad portions 4a and 4b on the turn-in side and the turn-out side can be uniformly leveled, and uneven wear of the friction pad 4 can be prevented in advance.

As described above, when the load generated by one actuator 2 and the load generated by the other actuator 2 are controlled to a predetermined ratio, the load control can be performed stably and easily.

A second application example will be described.
As shown in FIG. 20, the two motor drive control units 44A and 44A (FIG. 17) are configured so that the load generated by both actuators 2 and 2 (FIG. 17) until the second actuator 2-2 reaches the maximum load. May be controlled to be distributed at a constant ratio.

As shown in FIG. 21, the two motor drive control units 44A and 44A (FIG. 17) cause the load generated in the second actuator 2-2 to be applied to the first actuator 2-1. The load may be larger than the load to be generated, and control may be performed so that the load on both actuators 2 and 2 (FIG. 17) becomes maximum at the maximum point of the total load after the certain load.

In addition, the load correction of each actuator may be corrected not only by changing the ratio linearly but also by a curve (non-linear) as shown in FIGS. It can be appropriately changed according to the amount of wear. Further, after the vehicle is stopped, by making the load commands of both actuators the same, the load is concentrated only on the second actuator, and the life of the entire brake device can be prevented from being reduced.

A brake device according to a second application example of the present invention will be described with reference to FIGS. 15 and 22 referred to in the third embodiment. In the following description, portions corresponding to the matters described in the third embodiment and / or the first application example are denoted by the same reference numerals, and redundant descriptions are omitted. When only a part of the configuration is described, the other parts of the configuration are the same as those of the third embodiment and / or the first application unless otherwise specified.

The control device 5A of the brake device of the second application example corresponds to the output (brake command) of the sensor 34a that changes according to the operation amount of the brake operation means 34, the rotation speed and the rotation direction of the brake rotor 3 (FIG. 13). Thus, the magnitude of the drive signal is changed.

The control device 5A is given the rotational speed and direction of the brake rotor 3 (FIG. 13) from a wheel speed sensor 41 provided on each wheel. The control device 5A includes individual control units 57A and 57A different from those in the third embodiment. Each individual control unit 57A uniformly equalizes the wear amount of the feed-in side pad portion 4a (FIG. 13) and the wear amount of the feed-out side pad portion 4b (FIG. 13), thereby offsetting the friction pad 4 (FIG. 13). In order to prevent wear, the magnitude of the drive signal to the corresponding pressure-increasing linear valve 52 is changed according to the brake command and the rotational speed and direction of the brake rotor 3 (FIG. 13).

Similarly to the individual control unit 57 of the third embodiment, each individual control unit 57A of the second application example also detects the detected values of the first and second hydraulic sensors 55, 56 and the flow meters Sb1, Sb2 or the stroke sensor Sa1. Based on the amount of movement of the pistons 50, 50 calculated from the detected value of Sa2, the total wear amount of the pad portions 4a, 4a and the total wear amount of the pad portions 4b, 4b can be calculated.

When the total wear amount is equal to or greater than the threshold value, the control device 5A causes the warning display or the like output means 46 to output a warning display or the like. The driver of the vehicle can recognize that the wear limit of the friction pad 4 is close by the output warning display or the like.

As described above, the pistons 50 and 50 can be individually driven by the fluid pressure type drive units 58 and 58, and uneven wear of the friction pad 4 can be prevented beforehand. In addition, since the brake device can be configured using the existing fluid pressure actuator 2, the manufacturing cost can be reduced.

As the detection means, an encoder may be applied instead of the wheel speed sensor.
The rotation direction of the brake rotor may be indirectly determined from a sensor that detects the shift position of the vehicle.
The command value given to each actuator can be changed as appropriate so that uneven wear of the friction pad is less likely to occur depending on one or both of the vehicle speed and the magnitude of the brake command.

Examples of the application examples of the present invention described above include the following.

[Aspect 1]
Brake rotor 3,
A friction pad 4 that contacts the brake rotor 3 to generate a braking force;
Two actuators 2, 2 that respectively include pistons 18, 18 for driving the friction pad 4 to abut against and separate from the brake rotor 3 by the pistons 18, 18;
A control device 5 for controlling the two actuators 2 and 2 in accordance with a given brake command,
Detection means 41 for detecting the rotation speed and rotation direction of the brake rotor 3 is provided,
The control device 5 individually generates loads generated by the two actuators 2 and 2 according to the given brake command and the rotational speed and direction of the brake rotor 3 detected by the detection means 41. Brake device having individual control units 44A, 44A for controlling.
The rotation speed of the brake rotor 3 is synonymous with the number of rotations of the brake rotor 3 per unit time.

According to this configuration, the detection means 41 detects the rotation speed and the rotation direction of the brake rotor 3. Each of the individual control units 44A and 44A individually applies loads generated by the two actuators 2 and 2 according to the applied brake command and the rotation speed and rotation direction of the brake rotor 3 detected by the detection means 41. Control. The two individual units 44A and 44A control the ratio of the load generated by the two actuators 2 and 2 to a predetermined ratio, for example, according to the brake command and the rotational speed and direction of the brake rotor 3. The predetermined ratio is determined by at least one of testing, simulation, and design. Thus, by controlling the two actuators 2 and 2 individually, uneven wear of the friction pad 4 can be prevented beforehand. Thereby, drag torque can be reduced and the replacement time of the friction pad 4 can be delayed.

[Aspect 2]
In the brake device according to the first aspect, the two individual control units 44A and 44A apply the load of the actuator 2 corresponding to the pad portion 4b located on the downstream side in the rotation direction of the brake rotor 3 among the friction pads 4. The brake device which controls by the value larger than the load of the actuator 2 corresponding to the pad part 4a located in the rotation direction upstream in the said brake rotor 3. FIG.
When the friction pad 4 and the brake rotor 3 come into contact with each other, due to mutual friction, the pad portion 4a (the pad portion 4a on the turn-in side) located on the upstream side in the rotation direction of the brake rotor 3 among the friction pads 4 has a rotation direction Compared with the pad part 4b located on the downstream side (the pad part 4b on the delivery side), a force that is drawn into the brake rotor 3 acts. As a result, the pad portion 4a on the entry side may be more unevenly worn than the pad portion 4b on the return side.

In this case, the load of the actuator 2 corresponding to the pad portion 4b on the return side is controlled to a value larger than the load of the actuator 2 corresponding to the pad portion 4a on the return side, so that The amount of wear of the pad portions 4a and 4b on the side can be uniformly leveled, and uneven wear of the friction pad 4 can be prevented beforehand. Therefore, drag torque resulting from the progress of uneven wear of the friction pad 4 can be reduced, and the replacement time of the friction pad 4 can be delayed.

[Aspect 3]
In the brake device according to Aspect 1 or Aspect 2, the two individual control units 44A and 44A control the load generated by one actuator 2 and the load generated by the other actuator 2 to a predetermined ratio. .
The determined ratio is a value arbitrarily determined by design or the like, and is determined by obtaining an appropriate value by one or both of testing and simulation, for example.
According to this configuration, the ratio of the load of one actuator 2 and the load of the other actuator 2 is different from each other with respect to the total load, for example, depending on the brake command and the rotational speed and direction of the brake rotor 3. Controlled. Under different conditions such as a brake command, the load ratio of one actuator 2 and the load ratio of the other actuator 2 are controlled to the same ratio.
In this case, load control can be performed stably and easily.

[Aspect 4]
In the brake device according to any one of the aspects 1 to 3, the two individual control units 44A and 44A are regions in which a sum of loads generated by the two actuators 2 and 2 is equal to or less than a predetermined load. Then, the brake apparatus which controls only the load of the actuator 2 corresponding to the pad part 4b located in the rotation direction downstream side in the said brake rotor 3 among the said friction pads 4. FIG.
The determined load is a value arbitrarily determined by design or the like, and is determined by obtaining an appropriate value by one or both of testing and simulation, for example.
In this case, the wear amount of the pad portions 4a and 4b on the entrance side and the exit side can be evenly balanced, and load control can be easily performed.

[Aspect 5]
In the brake device according to any one of the aspects 1 to 4, the actuators 2 and 2 are configured so that the electric motors 11 and 11 and the rotational movements of the electric motors 11 and 11 are caused by the pistons 18 and 18. Brake device having linear motion mechanisms 12 and 12 for converting into linear motion.
Thus, in the 2-piston type electric actuator 2, uneven wear of the friction pad 4 can be prevented in advance.

[Aspect 6]
In the brake device according to any one of the aspects 1 to 4, the actuators 2 and 2 include fluid pressure type drive units 58 and 58 for driving the pistons 50 and 50, respectively, using fluid as a medium. Brake device.
In this case, the pistons 50 and 50 can be individually driven by the fluid pressure type drive parts 58 and 58, and uneven wear of the friction pad 4 can be prevented beforehand. In addition, since the brake device can be configured using an existing fluid pressure type actuator, the manufacturing cost can be reduced.

2 (2-1, 2-2) Actuator 3 Brake rotor 4 Friction pads 4a and 4b Pad portions 5 and 5A Control devices 44 and 57 Individual control portion 45 Pad portion wear amount estimation means

Claims (5)

1. A brake rotor,
   A friction pad including a plurality of pad portions, wherein the friction pad is brought into contact with the brake rotor to generate a braking force;
   Two actuators each including a piston, wherein each piston of the two actuators corresponds to a different pad portion of the plurality of pad portions, and the piston makes contact with the friction pad against the brake rotor Two actuators that drive apart,
   A control device for controlling the two actuators,
   Pad portion wear amount estimating means for estimating the wear amount of the pad portion corresponding to each piston of the two actuators, and the pad portion wear amount estimating means estimated by the pad portion wear amount estimating means according to a given brake command And a control device having an individual control unit for individually controlling the two actuators according to the amount of wear.
2. 2. The brake device according to claim 1, wherein each of the two actuators has a fluid pressure type drive unit that drives each piston using a fluid as a medium.
3. 2. The brake device according to claim 1, wherein each of the two actuators includes an electric motor and a linear motion mechanism that converts a rotational motion of the electric motor into a linear motion of each piston.
4. 4. The brake device according to claim 1, wherein the pad portion wear amount estimation means detects a remaining amount of the pad portion corresponding to each of the pistons. 5. Have
   The individual control unit is a load correction unit that corrects a load generated in the two actuators according to a difference in the remaining amount of the pad unit corresponding to each piston detected by the pad unit remaining amount detection unit. Brake device having.
5. 4. The brake device according to claim 1, wherein the individual control unit has the same protrusion amount of the pistons of the two actuators and is generated in each of the two actuators. 5. A brake device that controls the two actuators so that a total load to be applied coincides with a required load on the brake device.

Images