JP2019171956A - Brake device and electric brake device - Google Patents

Abstract

To provide a brake device which can suppress the generation of a cronk sound, and an electric brake device.SOLUTION: A brake device 1 comprises an inner brake pad 13 and an outer brake pad 14 for pressing a disc D which rotates together with the rotation of wheels, and a control device 16 for controlling the pressurization of the inner brake pad 13 and the outer brake pad 14 according to a brake requirement. When a vehicle speed or a wheel speed (vehicle speed V) is equal to a prescribed speed (speed threshold Va) or lower, and there is no brake requirement, the control device 16 makes the inner brake pad 13, the outer brake pad 14 and the disc D contact with one another by using a pressing force which does not contribute to a brake.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a brake device and an electric brake device that apply braking force to a vehicle such as an automobile.

  In general, a brake device provided in a vehicle such as an automobile is provided with a bracket arranged across the outer peripheral side of a disc rotating together with wheels in an axial direction, and opposed to both sides (inner side and outer side) of the disc supported by the bracket. A pair of brake pads arranged and a pressing mechanism (piston) for pressing the pair of brake pads against the disc are provided. In response to a braking request, the brake device propels the brake pad toward the disc and applies a braking force to the traveling vehicle by pressing the brake pad against the disc.

  In this case, when the brake pad comes into contact with the rotating disk, the brake pad is dragged by the rotating disk and collides with the bracket, so that there is a possibility that a cronk sound (collision sound) is generated. Therefore, in Patent Document 1, when it is detected that the traveling direction of the vehicle is reversed, the pressing mechanism presses the brake pad toward the disk in advance and moves the brake pad to the rotation side of the disk in the rotation direction. Yes. As a result, when the driver performs a brake operation, the kinetic energy at which the brake pad collides with the bracket is reduced to suppress the generation of a cronk sound.

Japanese Unexamined Patent Publication No. 2006-68591

  By the way, in the brake device described in Patent Document 1, when it is not possible to acquire a signal for detecting that the traveling direction of the vehicle is reversed, it may be difficult to move the brake pad in the disc rotation direction. . In particular, if the vehicle is turned off after the vehicle is parked with the vehicle retracted, the memory when the vehicle is retracted is reset, and the vehicle traveling direction is reversed when the vehicle is subsequently moved forward. There is a possibility that a signal for detecting whether or not can be acquired.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a brake device and an electric brake device that can suppress the generation of a cronk noise.

  In order to solve the above-described problem, the present invention provides a brake device including a friction member that presses a rotating member that rotates with the rotation of a wheel, and a control device that controls the pressing of the friction member in response to a braking request. The control device contacts the friction member and the rotating member with a pressing force that does not contribute to braking when the vehicle speed or wheel speed is equal to or lower than a predetermined speed and there is no braking request.

  In another aspect of the invention, a friction member that presses a rotating member that rotates with the rotation of a wheel, an electric motor that propels the friction member in response to a braking request and applies thrust to a piston for pressing the rotating member, An electric brake device comprising: a control device that controls pressing of the electric motor; wherein the control device drives the electric motor when the vehicle speed or wheel speed is equal to or lower than a predetermined speed and there is no braking request, and the thrust does not contribute to braking. The piston is pushed to bring the friction member and the rotating member into contact with each other.

  According to the present invention, it is possible to suppress the generation of cron noise during brake operation.

It is explanatory drawing which shows the system configuration | structure of the electric brake device by the 1st Embodiment of this invention. It is a flowchart of the pressing force generation control which the control apparatus in FIG. 1 performs. It is explanatory drawing which shows the system configuration | structure of the hydraulic brake device by the 2nd Embodiment of this invention.

  Hereinafter, an example in which the brake device according to the embodiment is applied to a four-wheeled vehicle will be described with reference to the accompanying drawings.

  1 and 2 show a first embodiment of the present invention. The brake device 1 is mounted on a vehicle and is an electric brake device that electrically applies a braking force. The brake device 1 includes a brake pedal 2, a braking operation amount detector 3, a vehicle speed detector 4, an electric brake caliper 5, and a control device 16.

  The brake pedal 2 is a braking operation member that is provided side by side with an accelerator pedal (not shown) arranged in front of the driver's seat and that is operated by stepping when the driver decelerates the vehicle (when a braking request is made). is there. The braking operation amount detector 3 is provided, for example, on the brake pedal 2 and detects the braking operation amount of the brake pedal 2. The brake operation amount detector 3 includes, for example, a brake pedal depression force sensor that detects an operation force of the brake pedal 2 and a brake pedal stroke sensor that detects an operation amount of the brake pedal 2. The braking operation amount detector 3 outputs the detected braking operation amount to the control device 16.

  The vehicle speed detector 4 detects a vehicle speed or a wheel speed. For example, the vehicle speed detector 4 detects a vehicle speed by detecting a wheel speed sensor that detects a rotational speed of a wheel or an absolute position of the vehicle. It is configured. The vehicle speed detector 4 outputs the detected vehicle speed V to the control device 16.

  The electric brake caliper 5 applies a braking force to the disk D (rotating member) that rotates with the wheel, and is controlled by the control device 16. The electric brake caliper 5 strides over the outer periphery of the disk D that moves forward when rotating in the direction indicated by an arrow A in FIG. 1 and moves backward when rotating in the direction opposite to the direction indicated by the arrow A, for example. It is provided as follows. The electric brake caliper 5 includes an electric motor 6, a rotation angle detector 7, a speed reducer 8, a bracket 9, a caliper body 10, a piston 11, a rotation / linear motion converter 12, an inner brake pad 13, an outer brake pad 14, and The pressing force detector 15 is included.

  The electric motor 6 is an electric motor serving as a drive source for propelling a piston 11 described later. The electric motor 6 generates a torque for achieving a pressing force with which the piston 11 presses the inner brake pad 13 in accordance with a braking command output from the control device 16. The rotation angle detector 7 detects a rotation angle of a rotation shaft (not shown) of the electric motor 6, and is composed of, for example, a rotation angle sensor. The rotation angle detector 7 outputs the detected rotation angle to the control device 16. The speed reducer 8 converts the torque generated by the electric motor 6 in accordance with the speed reduction ratio, and includes, for example, a spur multi-stage speed reduction mechanism and a planetary gear speed reduction mechanism. The speed reducer 8 may be configured by a pulley speed reduction mechanism. The reducer 8 decelerates and enhances the rotation of the electric motor 6 at a predetermined reduction ratio, and transmits it to the rotary / linear motion converter 12 described later.

  The bracket 9 is attached to the non-rotating part of the vehicle so as to straddle the outer periphery of the disk D. The bracket 9 includes an inner side support portion 9A that supports an inner brake pad 13 described later, and an outer side support portion 9B that supports an outer brake pad 14 described later. The inner side support portion 9A and the outer side support portion 9B are respectively formed in a concave shape at a position sandwiching the disk D, and the inner brake pad 13 and the outer brake pad 14 are supported movably in the axial direction of the disk D. Yes.

  The caliper body 10 is attached to the bracket 9 so as to be movable in the axial direction of the disk D. That is, the bracket 9 and the caliper body 10 are caliper floating type disc brakes. The caliper body 10 extends from the cylinder portion 10A to the outer side across the outer peripheral side of the disk D and is disposed at the distal end side outside the vehicle. The claw portion 10B is integrally formed.

  In the cylinder portion 10A, a piston 11 formed in a cup shape with a bottom is accommodated so as to be movable in the axial direction of the disk D. The piston 11 is provided so as to face an inner brake pad 13 which will be described later in the axial direction of the disk D, and presses the inner brake pad 13 by moving toward the disk D. In this case, the claw portion 10 </ b> B presses the outer brake pad 14 against the disk D by the caliper body 10 moving toward the inner side with respect to the bracket 9 by the reaction force against the pressing force applied to the inner brake pad 13 by the piston 11.

  The rotation / linear motion converter 12 includes, for example, a ball screw mechanism, and converts the rotational motion transmitted from the electric motor 6 to the speed reducer 8 into a linear motion. The rotary / linear motion converter 12 is provided in the cylinder portion 10A and a push rod 12A that has a proximal end connected to the speed reducer 8 and a distal end that contacts the piston 11 provided in the cylinder portion 10A of the caliper body 10. A base nut 12B that is screw-engaged with the outer peripheral side of the push rod 12A. The rotary / linear motion converter 12 propels the piston 11 toward the disk D by the push rod 12A moving forward while rotating relative to the base nut 12B.

  The inner brake pad 13 and the outer brake pad 14 are friction members that apply a braking force by pressing the disk D that rotates as the wheels rotate. The inner brake pad 13 is located between the piston 11 and the disk D and is provided on the inner side support portion 9 </ b> A of the bracket 9. The inner brake pad 13 includes a back plate 13A in which both end sides in the disc rotation direction (upward and downward in FIG. 1) are slidably inserted into the inner side support portion 9A, and a disc D fixed to the back plate 13A. And a lining 13B in frictional contact. In the inner brake pad 13, the lining 13 </ b> B is brought into frictional contact with one surface of the disk D when the back plate 13 </ b> A is pressed by the piston 11. Further, as shown in FIG. 1, a gap S is formed between the back plate 13A and the inner support portion 9A so that the inner brake pad 13 slides smoothly in the axial direction of the disk D.

  On the other hand, the outer brake pad 14 is located between the claw portion 10B and the disk D and is provided on the outer side support portion 9B of the bracket 9. The outer brake pad 14 includes a back plate 14A in which both end sides in the disc rotation direction (upward and downward in FIG. 1) are slidably inserted into the outer side support portion 9B, and a disc D fixed to the back plate 14A. And a lining 14B in frictional contact. In the outer brake pad 14, the lining 14B is brought into frictional contact with the other surface of the disk D when the back plate 14A is pressed against the claw portion 10B. Further, as shown in FIG. 1, a gap S is formed between the back plate 14A and the outer side support portion 9B so that the outer brake pad 14 slides smoothly in the axial direction of the disk D.

  The pressing force detector 15 is provided on the push rod 12A of the rotary / linear motion converter 12, and includes, for example, a pressing force sensor using a load cell. The pressing force detector 15 detects a reaction force against the pressing force from the piston 11 to the inner brake pad 13 and the outer brake pad 14. That is, when the disc D is sandwiched between the inner brake pad 13 and the outer brake pad 14 and braking force starts to be generated, the reaction force is applied to the pressing force detector 15 via the push rod 12A. Then, the pressing force detector 15 outputs the detected pressing force to the control device 16 described later.

  Next, the control device 16 that controls the electric brake caliper 5 will be described.

  The control device 16 presses the inner brake pad 13 and the outer brake pad 14 toward the disc D in response to a braking request. In the control device 16, the braking operation amount detector 3, the vehicle speed detector 4, the rotation angle detector 7, and the pressing force detector 15 are connected to the input side, and the electric motor 6 is connected to the output side. The control device 16 receives the signal output from the braking operation amount detector 3 and calculates a target braking force (pressing force) for each wheel according to a control program stored (stored) in the memory 16A in advance. .

  Then, the control device 16 outputs a braking command to the electric motor 6 based on the calculated target braking force. Further, the control device 16 receives the rotation angle of the electric motor 6 from the rotation angle detector 7 and receives the pressing force of the inner brake pad 13 and the outer brake pad 14 from the pressing force detector 15 to achieve the target braking force. Thus, the electric motor 6 is controlled. In this case, the control device 16 receives the vehicle speed or the wheel speed from the vehicle speed detector 4 and monitors whether or not the vehicle is decelerating.

  In addition, the control device 16 can detect the inner brake pad 13 and the outer brake even when there is no braking request when the vehicle speed V detected by the vehicle speed detector 4 is equal to or lower than the speed threshold Va (predetermined speed) (V ≦ Va). The pad 14 is brought into contact with the disk D with a pressing force that does not contribute to braking (a pressing force that does not generate braking force). For this purpose, the control device 16 is provided with a pad moving unit 16B that drives the electric motor 6 so as to generate a pressing force that does not contribute to braking.

  The speed threshold Va is set to the speed at which the vehicle starts to move (immediately after starting the vehicle), and is stored in advance in the memory 16A of the control device 16. As an example, the speed threshold value Va is set as a low speed of about 3 km to 5 km per hour, for example. In addition, the memory 16A stores a control program for pressing force generation control shown in FIG. The pad moving unit 16B of the control device 16 causes the inner brake pad 13 and the outer brake pad 14 to move at a low speed when the vehicle speed V is equal to or lower than the speed threshold Va, according to the control program for pressing force generation control stored in the memory 16A. Slightly (slowly) contact the rotating disk D.

  That is, the inner brake pad 13 and the outer brake pad 14 are in frictional contact with the disk D with a pressing force that does not apply a braking force (hereinafter referred to as a non-braking pressing force). This non-braking pressing force is set by experiment, calculation, simulation, or the like as a value that does not affect the braking of the disk D, that is, a value that does not decelerate the vehicle, and is stored in the memory 16A.

  Thereby, the inner brake pad 13 is dragged by the rotation of the disk D and moves to a position close to the inner side support portion 9A on the delivery side in the rotation direction of the disk D. On the other hand, the outer brake pad 14 is dragged by the rotation of the disc D and moves to a position close to the outer side support portion 9B on the delivery side in the rotation direction of the disc D.

  Then, the pad moving unit 16B releases the non-braking pressing force between the inner brake pad 13 and the outer brake pad 14 when the vehicle speed V becomes larger than the speed threshold Va. As a result, the inner brake pad 13 and the outer brake pad 14 move away from the disk D and come out of contact with the disk D.

  In this manner, the pad moving unit 16B of the control device 16 drives the electric motor 6 when the vehicle is at a low speed, and moves the inner brake pad 13 and the outer brake pad 14 in the rotational direction of the disk D in advance. As a result, when the brake operation is performed thereafter, the kinetic energy at which the inner brake pad 13 and the outer brake pad 14 collide with the inner side support portion 9A and the outer side support portion 9B can be reduced. Generation of sound can be suppressed.

  The brake device 1 according to the present embodiment has the above-described configuration, and the operation thereof will be described next.

  When the driver depresses the brake pedal 2, the braking operation amount detector 3 detects the operation amount of the brake pedal 2 and outputs the operation amount to the control device 16. The control device 16 calculates a target braking force based on the operation amount detected by the braking operation amount detector 3. Then, the control device 16 outputs a braking command based on the calculated target braking force to the electric motor 6. The electric motor 6 is rotationally driven in the positive direction (apply direction) based on a braking command from the control device 16, and the rotation is reduced and enhanced at a predetermined reduction ratio by way of the reduction gear 8. Then, the rotation of the speed reducer 8 is transmitted to the push rod 12A of the rotary / linear motion converter 12.

  The push rod 12A moves forward while rotating relative to the base nut 12B, thereby pressing the piston 11 toward the disk D. As a result, the piston 11 presses the inner brake pad 13 against the disk D. The caliper body 10 moves to the right in FIG. 1 with respect to the bracket 9 by a reaction force against the pressing force of the piston 11 on the inner brake pad 13, and the claw portion 10 </ b> B presses the outer brake pad 14 against the disk D. . As a result, the disk D is sandwiched between the inner brake pad 13 and the outer brake pad 14, and a frictional force is generated to generate a braking force on the vehicle.

  In this case, the pressing force detector 15 detects the pressing force applied to the disk D from the inner brake pad 13 and the outer brake pad 14 by the propulsion of the piston 11 and outputs the detected pressing force to the control device 16. The rotation angle detector 7 detects the rotation angle of the rotation shaft of the electric motor 6 and outputs it to the control device 16. The control device 16 monitors the detected values and controls the electric motor 6 so as to satisfy the target braking force.

  On the other hand, at the time of releasing the brake when the brake pedal 2 is not operated, the rotation shaft of the electric motor 6 rotates in the reverse direction (release direction) according to the brake release command from the control device 16, and the rotation in the reverse direction is reduced. 8 to the push rod 12A. As a result, the push rod 12A moves backward while rotating in the opposite direction relative to the base nut 12B, so that the piston 11 moves away from the disk D, and the inner brake pad 13 and the outer brake pad 14 to the disk D move. The braking force is released.

  By the way, in Patent Document 1 described above, when it is detected that the traveling direction of the vehicle is reversed, the brake pad is pressed toward the disc, and the brake pad is moved in the disc rotation direction in advance. Thereby, when a driver | operator performs brake operation, the kinetic energy at the time of a brake pad colliding with a bracket is reduced, and generation | occurrence | production of a crank sound is suppressed.

  However, in the brake device described in Patent Document 1, if a signal for detecting that the traveling direction of the vehicle is reversed cannot be acquired, it may be difficult to move the brake pad in the disc rotation direction. . In particular, if the vehicle is turned off after the vehicle is parked with the vehicle retracted, the memory when the vehicle is retracted is reset, and the vehicle traveling direction is reversed when the vehicle is subsequently moved forward. There is a possibility that a signal for detecting whether or not can not be acquired.

  Therefore, in the present embodiment, when the vehicle speed or wheel speed is equal to or lower than a predetermined speed and there is no braking request, the brake pads 13 and 14 and the disk D are brought into contact with each other with a pressing force that does not contribute to braking. Specifically, the control device 16 drives the motor 6 when the vehicle speed or the wheel speed (vehicle speed V) is equal to or lower than a predetermined speed (speed threshold Va) (V ≦ Va) and no braking request is made, and does not contribute to braking. The piston 11 is propelled by thrust to bring the brake pads 13 and 14 into contact with the disk D. Thereby, generation | occurrence | production of a cronk sound can be suppressed, without acquiring the information of the advancing direction of a vehicle, and the reliability of a brake device can be improved.

  Next, the pressing force generation control performed by the control device 16 will be described with reference to FIG. The control process shown in FIG. 2 is repeatedly executed at a predetermined control period while the vehicle is powered on.

  In step 1, it is determined whether or not there is a braking operation. That is, the control device 16 determines whether or not the brake pedal 2 is depressed by the driver, and the braking operation amount detector 3 outputs a braking request signal. In this case, the control device 16 determines whether or not the brake pedal 2 is operated (braking operation) by determining whether or not the detection value detected by the braking operation amount detector 3 is equal to or greater than a predetermined depression threshold value. Can be determined. If “YES” in step 1, that is, if it is determined that there is no braking operation, the process proceeds to step 2. On the other hand, if “NO” in step 1, that is, if it is determined that there is a braking operation, the process proceeds to step 5.

  In step 2, it is determined whether or not the vehicle speed V is equal to or lower than the speed threshold Va (V ≦ Va). That is, the pad moving unit 16B of the control device 16 determines whether or not the vehicle speed V detected by the vehicle speed detector 4 is equal to or less than the speed threshold value Va stored in the memory 16A. The speed threshold Va is set to a low speed of about 3 to 5 km / h, for example, as the speed at which the vehicle starts to move. If “YES” in step 2, that is, if it is determined that the vehicle speed V is equal to or less than the speed threshold Va (V ≦ Va), the process proceeds to step 3. On the other hand, if “NO” in step 2, that is, if it is determined that the vehicle speed V is larger than the speed threshold Va (V> Va), the process proceeds to step 4.

  In step 3, pad movement pressing force generation control is performed. That is, the pad moving unit 16B of the control device 16 starts to drive the electric motor 6 to rotate forward (apply direction) even if the brake pedal 2 is not operated in order to generate a predetermined non-braking pressing force. Output a signal. As a result, the rotation axis of the electric motor 6 is driven to rotate in the forward direction, and the rotation is transmitted to the push rod 12 </ b> A via the speed reducer 8. The push rod 12A advances while pressing relative to the base nut 12B and presses the piston 11.

  The piston 11 presses the inner brake pad 13 toward the disk D. Further, the claw portion 10 </ b> B presses the outer brake pad 14 toward the disk D by a reaction force against the pressing force applied to the inner brake pad 13 by the piston 11. In this case, the control device 16 monitors the pressing force against the disc D of the inner brake pad 13 and the outer brake pad 14 output from the pressing force detector 15 and controls the electric motor 6 to satisfy the non-braking pressing force. Output a signal.

  As a result, the inner brake pad 13 is dragged in the rotational direction of the disk D and moves until the back plate 13A comes close to the inner side support portion 9A on the delivery side of the disk D. Similarly, the outer brake pad 14 is dragged in the rotational direction of the disk D and moves until the back plate 14A comes close to the outer side support portion 9B on the delivery side of the disk D.

  That is, as shown in FIG. 1, for example, when the disk D rotates in the direction opposite to the direction indicated by the arrow A, when the inner brake pad 13 comes into frictional contact with the disk D, the inner brake pad 13 and the back plate 13A It moves to close the gap S between the side support portions 9A. In this case, the disk D rotates at a low speed of about 3 to 5 km / h, and the inner brake pad 13 is pressed against the disk D with a non-braking pressing force that does not contribute to braking.

  Thereby, since the inner brake pad 13 moves with small kinetic energy toward the inner side support portion 9A, it is possible to suppress the occurrence of a collision sound when the back plate 13A collides with the inner side support portion 9A. As with the inner brake pad 13, the outer brake pad 14 moves toward the outer side support portion 9B so as to close the gap S. Then, when the pad movement pressing force generation control in step 3 is completed, the process returns.

  In step 4, the clearance between the disk D and the brake pads 13 and 14 is ensured. That is, the pad moving unit 16B of the control device 16 outputs a control signal for starting reverse rotation (release direction) to the electric motor 6 in order to move the piston 11 away from the disk D. Thereby, the rotation of the electric motor 6 is transmitted to the push rod 12 </ b> A via the speed reducer 8. The push rod 12A moves backward while rotating relative to the base nut 12B to release the pressure of the piston 11.

  As a result, the inner brake pad 13 is released from the pressure from the piston 11, so that the inner brake pad 13 moves away from the disk D and a clearance is secured between the inner brake pad 13 and the disk D. On the other hand, the outer brake pad 14 moves away from the disk D and moves away from the disk D because the reaction force against the pressing force applied to the inner brake pad 13 by the piston 11 disappears and the pressing from the claw portion 10B is released. Clearance is ensured.

  Thereby, it can suppress that the state which the brake pads 13 and 14 contacted the disk D is maintained during driving | running | working of a vehicle. Then, the inner brake pad 13 and the outer brake pad 14 can be set in a standby (preparation) state for a brake operation in a state where the inner brake pad 13 and the outer brake pad 14 are offset toward the delivery side of the disk D. When the clearance in step 4 is completed, a return is made.

  In step 5, pressure generation control according to the amount of braking operation is performed. That is, the control device 16 outputs a control signal for starting the forward rotation to the electric motor 6 based on the operation amount of the brake pedal 2 detected by the braking operation amount detector 3. In this case, the rotating shaft of the electric motor 6 rotates forward so as to generate a pressing force that applies a braking force to the disk D. The rotation of the electric motor 6 is transmitted to the piston 11 via the speed reducer 8 and the push rod 12A, and the piston 11 presses the inner brake pad 13 toward the disk D. Further, the claw portion 10B of the caliper body 10 presses the outer brake pad 14 toward the disk D by the reaction force at this time.

  In this case, the inner brake pad 13 has a small clearance S between the back plate 13A and the inner side support portion 9A on the delivery side in the rotation direction of the disk D by the control in step 3. That is, the inner brake pad 13 moves toward the disc D from a position offset from the inner side support portion 9A on the delivery side in the rotation direction of the disc D. As a result, when the lining 13B of the inner brake pad 13 is brought into frictional contact with the disk D, the kinetic energy that the back plate 13A of the inner brake pad 13 collides with the inner support portion 9A is reduced, and the generation of a crank noise is suppressed. be able to.

  On the other hand, the outer brake pad 14 moves toward the disc D from a position offset to the outer side support portion 9B on the delivery side in the rotation direction of the disc D. As a result, when the lining 14B of the outer brake pad 14 comes into frictional contact with the disk D, the kinetic energy with which the back plate 14A of the outer brake pad 14 collides with the outer side support portion 9B is reduced, and the generation of a crank noise is suppressed. be able to.

  Thereafter, when detecting that the operation of the brake pedal 2 has been released, the control device 16 reversely rotates the electric motor 6 so that the disc D and the brake pads 13 and 14 are not in contact with each other, thereby releasing the braking. When step 5 is completed, a return is returned.

  Thus, in the present embodiment, when the vehicle speed V is equal to or less than the speed threshold Va and there is no braking request, the control device 16 brings the brake pads 13 and 14 into contact with each other so as not to apply the braking to the disk D. 14 is moved to the delivery side of the disk D. Thereby, generation | occurrence | production of the cronk sound at the time of brake operation can be suppressed. Further, since the traveling direction information of the vehicle is unnecessary, the positions of the brake pads 13 and 14 can be controlled without any confusion even when the vehicle power is turned off, for example, due to parking. Further, immediately after the start of the vehicle, the clearance between the brake pads 13 and 14 and the disk D is reduced, so that, for example, the responsiveness when the automatic brake is activated immediately after the start of the vehicle is increased and the stop distance is shortened. be able to.

  Next, FIG. 3 shows a second embodiment of the present invention. A feature of the second embodiment is that a hydraulic brake device that presses a brake pad by hydraulic pressure is used. In the second embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof is omitted.

  The brake device 21 is mounted on a vehicle and is a hydraulic brake device that applies a braking force by hydraulic pressure. The brake device 21 includes a brake pedal 2, a braking operation amount detector 3, a vehicle speed detector 4, a hydraulic unit 22, a hydraulic brake caliper 23, and a control device 26.

  The hydraulic unit 22 includes, for example, an electric booster and a skid prevention device, and is connected to the cylinder portion 10A of the caliper body 10 via a hydraulic line 22A. The hydraulic unit 22 supplies oil fluid (brake fluid) to the cylinder portion 10A of the caliper body 10 based on a fluid pressure command output from a control device 26 described later.

  The hydraulic brake caliper 23 applies a braking force to the disk D with the oil supplied from the hydraulic unit 22. The hydraulic brake caliper 23 is provided so as to straddle the outer periphery of the disk D. The hydraulic brake caliper 23 includes a bracket 9, a caliper body 10, a piston 11, an inner brake pad 13, an outer brake pad 14, a piston position detector 24, and a pressing force detector 25.

  The piston position detector 24 is provided in the cylinder portion 10 </ b> A of the caliper body 10. The piston position detector 24 detects the position of the piston 11 that moves in the cylinder portion 10A, and includes, for example, a displacement sensor, a flow rate sensor that detects the flow rate of oil supplied to the cylinder portion 10A, and the like. Yes. The piston position detector 24 outputs the detected position information of the piston 11 to the control device 26 described later.

  The pressing force detector 25 is provided in the cylinder portion 10 </ b> A of the caliper body 10 at a position different from the piston position detector 24. The pressing force detector 25 detects a reaction force against the pressing force (thrust) from the piston 11 to the inner brake pad 13 and the outer brake pad 14. The pressing force detector 25 outputs the detected pressing force to the control device 26 described later.

  The control device 26 controls the pressing of the inner brake pad 13 and the outer brake pad 14 against the disc D in response to a braking request. In the control device 26, the braking operation amount detector 3, the vehicle speed detector 4, the piston position detector 24, and the pressing force detector 25 are connected to the input side, and the hydraulic unit 22 is connected to the output side. The control device 26 receives the signal output from the braking operation amount detector 3 and calculates a target braking force (pressing force) for each wheel according to a control program stored (stored) in the memory 26A in advance. .

  Then, the control device 26 outputs a braking command to the hydraulic unit 22 based on the calculated target braking force. Further, the control device 26 receives the position of the piston 11 from the piston position detector 24 and receives the pressing force of the inner brake pad 13 and the outer brake pad 14 from the pressing force detector 25 so that the target braking force is achieved. The hydraulic unit 22 is controlled. In this case, the control device 26 receives the vehicle speed or the wheel speed from the vehicle speed detector 4 and monitors whether or not the vehicle is decelerating.

  Further, the control device 26 detects that the inner brake pad 13 and the outer brake are not required even when there is no braking request when the vehicle speed V detected by the vehicle speed detector 4 is equal to or lower than the speed threshold Va (predetermined speed) (V ≦ Va). The pad 14 is brought into contact with the disk D with a pressing force that does not contribute to braking (a pressing force that does not generate braking force). For this purpose, the control device 26 is provided with a pad moving portion 26B that drives the hydraulic unit 22 so as to generate a pressing force that does not contribute to braking.

  The memory 26A stores a control program for pressing force generation control shown in FIG. The pad moving unit 26B of the control device 26 uses the control program for pressing force generation control stored in the memory 26A to change the inner brake pad 13 when the vehicle speed V is equal to or lower than the speed threshold Va (that is, when the vehicle is at a low speed). And the outer brake pad 14 are slightly (slowly) in contact with the disk D rotating at a low speed.

  In this case, the pad moving unit 26B of the control device 26 outputs a control signal for driving the hydraulic unit 22 even when the brake pedal 2 is not operated in order to generate a predetermined non-braking pressing force. As a result, the hydraulic unit 22 supplies oil for causing the piston 11 to generate non-braking pressing force to the cylinder portion 10A via the hydraulic line 22A.

  When the hydraulic pressure in the cylinder portion 10A increases, the piston 11 presses the inner brake pad 13 toward the disk D. Further, the claw portion 10 </ b> B presses the outer brake pad 14 toward the disk D by a reaction force against the pressing force applied to the inner brake pad 13 by the piston 11. In this case, the control device 26 monitors the pressing force of the inner brake pad 13 and the outer brake pad 14 that are output from the pressing force detector 25 against the disc D, and causes the hydraulic unit 22 to satisfy the non-braking pressing force. Output a control signal.

  As a result, the inner brake pad 13 is dragged in the rotational direction of the disk D and moves until the back plate 13A comes close to the inner side support portion 9A on the delivery side of the disk D. Similarly, the outer brake pad 14 is dragged in the rotational direction of the disk D and moves until the back plate 14A comes close to the outer side support portion 9B on the delivery side of the disk D.

  Thereafter, when the vehicle speed V becomes larger than the speed threshold Va, the pad moving part 26B of the control device 26 returns the oil liquid from the cylinder part 10A to the hydraulic unit 22 in order to move the piston 11 away from the disk D. Output a control signal. As a result, the inner brake pad 13 is released from the pressure from the piston 11, so that the inner brake pad 13 moves away from the disk D and a clearance is secured between the inner brake pad 13 and the disk D. On the other hand, the outer brake pad 14 moves away from the disk D and moves away from the disk D because the reaction force against the pressing force applied to the inner brake pad 13 by the piston 11 disappears and the pressing from the claw portion 10B is released. Clearance is ensured.

  Thus, also in the brake device 21 according to the second embodiment configured as described above, the brake pads 13 and 14 are moved to the delivery side of the disk D before the brake operation, as in the first embodiment. ing. This reduces the kinetic energy when the inner brake pad 13 and the outer brake pad 14 collide with the inner side support portion 9A and the outer side support portion 9B of the bracket 9 during the brake operation, respectively, and suppresses the generation of a cronk sound. be able to. Further, since the traveling direction information of the vehicle is unnecessary, the positions of the brake pads 13 and 14 can be controlled without any confusion even when the vehicle power is turned off, for example, due to parking. Further, immediately after the start of the vehicle, the clearance between the brake pads 13 and 14 and the disk D is reduced, so that, for example, the responsiveness when the automatic brake is activated immediately after the start of the vehicle is increased and the stop distance is shortened. be able to.

  In the first embodiment described above, the movement control of the brake pads 13 and 14 is described as an example when the vehicle speed V is equal to or less than the speed threshold Va. However, the present invention is not limited to this. For example, the movement control of the brake pads 13 and 14 is not performed when the vehicle decelerates to become the speed threshold Va or less, but only when the vehicle speed V increases. You may do it. That is, the movement control of the brake pads 13 and 14 may be performed when the vehicle starts and the vehicle speed V is equal to or less than the speed threshold Va. The same applies to the second embodiment.

  Further, in the first embodiment described above, the case where detection values such as the braking operation amount, the vehicle speed V, the rotation angle, and the pressing force are input to the control device 16 has been described as an example. However, the present invention is not limited to this, and for example, these detection values may be input to the control device 16 via another control device. The same applies to the second embodiment.

  As the brake device and the electric brake device based on the above-described embodiment, for example, the following modes can be considered.

  As a first aspect, in a brake device comprising: a friction member that presses a rotating member that rotates with the rotation of a wheel; and a control device that controls the pressing of the friction member in response to a braking request, the control device includes: When the vehicle speed or the wheel speed is equal to or less than a predetermined speed and there is no braking request, the friction member and the rotating member are brought into contact with each other with a pressing force that does not contribute to braking.

  As a second aspect, a friction member that presses a rotating member that rotates with rotation of a wheel, an electric motor that propels the friction member in response to a braking request and applies a thrust to a piston for pressing the rotating member, An electric brake device comprising: a control device that controls pressing of the electric motor; wherein the control device drives the electric motor when the vehicle speed or wheel speed is equal to or lower than a predetermined speed and there is no braking request, and the thrust does not contribute to braking. The piston is pushed to bring the friction member and the rotating member into contact with each other.

1,21 Brake device 6 Electric motor 11 Piston 13 Inner brake pad (friction member)
14 Outer brake pad (friction member)
16, 26 Control device D disk (rotating member)

Claims (2)

A friction member that presses a rotating member that rotates with the rotation of the wheel;
In a brake device comprising: a control device that controls pressing of the friction member in response to a braking request;
The said control apparatus makes the said friction member and the said rotation member contact with the pressing force which does not contribute to braking, when the vehicle speed or wheel speed is below a predetermined speed, and there is no said braking request | requirement, The brake device characterized by the above-mentioned. A friction member that presses a rotating member that rotates with the rotation of the wheel;
An electric motor for propelling the friction member in response to a braking request and applying thrust to a piston for pressing the rotating member;
In an electric brake device comprising a control device for controlling the pressing of the electric motor,
The control device drives the electric motor when the vehicle speed or the wheel speed is equal to or less than a predetermined speed and does not require the braking, and propels the piston with a thrust that does not contribute to braking to bring the friction member and the rotating member into contact with each other. An electric brake device characterized by that.

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