JP4937972B2 - Electric disc brake device - Google Patents

Description

  The present invention relates to a braking device such as an automobile, and more particularly to an electric disc brake device that suppresses rotation by a friction material being pressed against a braking rotator by a pressing member.

Conventionally, as a technique of an electric disc brake device, for example, as disclosed in Patent Document 1, a structure is disclosed in which an electric motor is used as a driving force and a plurality of pistons arranged in parallel are operated to make a friction pad slidably contact a disc rotor. ing.
Patent Document 2 focuses on the problem of heat exerted on a brake caliper using an electric motor as a driving force of a brake, and uses a heat insulating material or the like as a pressing member for preventing heat generated in the friction pad from being transmitted to the drive unit of the caliper. A structure is disclosed.
JP-T-2006-501413 JP 2000-213575 A

  However, although the structure of the above document discloses a structure in which a plurality of pistons arranged in parallel are driven by a common electric motor, the problem of surface pressure acting on the friction pad due to the pressure of the piston of the disc brake is disclosed. It has not been.

  For example, in a disc brake that presses the friction pad 3 against the disc rotor 2 as shown in FIGS. 9 (a) and 9 (b), the side where the disc rotor 2 enters the disc brake is defined as the entrance side, and the exit side is the exit side. In the electric disc brake as disclosed in Patent Document 1, for example, a vehicle is used because a larger force acts on the contact surface between the friction pad 3 on the entry side and the disc rotor 2 than on the delivery side. When the motor is running at a high speed, or when it is operated so that the same pressing force is generated in the two motors by applying a heavy load such as a sudden brake operation even at a low speed, the sliding surface of the friction pad 3 is As a result, the surface pressure acting on the inflow side and the outflow side becomes unbalanced, and the wear of the friction pad on the inflow side becomes more intense than the friction pad on the outflow side, which may cause uneven wear on the friction pad. . Also, it is conceivable to offset the pressing force on the delivery side so that uneven wear does not occur at high loads, but in this case, a large pressing force acts on the delivery side at low loads. There is a risk of uneven wear.

As engagement Ru configuration in the present invention in order to solve the above problems, a friction pad provided to be brought into sliding contact with the disc rotor from the respective working portion and reaction portion of the caliper body, a pressing member for pressing the friction pad, provided work for side, rotating-in side of the disc rotor for generating a pressing force to push member, a drive means comprising at least a first and a second drive unit arranged in each of the run-out side, drive motion means An electric disc brake device having a control unit that controls the load, a load sensor capable of detecting the actual pressing force on the turn-in side and the turn-out side applied to the friction pad of the drive unit, wheel speed And a storage means for storing command value data for obtaining a correction pressing force necessary to be applied to a preset friction pad. The command value data includes a wheel speed and an actual pressing force. At least As one of them increases, the wheel speed, the actual pressing force, and the correction pressing force are adjusted so that the correction pressing force on the delivery side that presses the pressing member has a larger increasing rate than the correction pressing force on the feeding side. The relationship with the pressure is set corresponding to the turn-in side and the turn-out side, and the control unit rotates the wheel speed detected by the wheel speed sensor and the clamp load on the turn-in side detected by the load sensor. With reference to the command value data stored in the storage means, the actual pressing force on the inlet side and the actual pressing force on the unwinding side as the clamping load on the unwinding side, at least one of the wheel speed and the actual pressing force is large. Accordingly, the electric drive disc that controls the first and second drive units so that the correction pressing force on the delivery side that presses the pressing member has a larger increase rate of the correction pressing force than the correction pressing force on the entry side. Brake device.
According to the present invention, the first and second drive units are arranged on the entrance side and the exit side of the disk rotor, and command value data for controlling the first and second drive units is stored in the storage unit of the control unit. By setting and storing in advance, the first and second drive units are individually controlled based on the command value data, and the friction pads are applied to the disc rotor with different pressing forces on the inlet side and outlet side, respectively. By sliding in contact, uneven wear of the friction pad can be prevented. That is, based on the actual pressing force applied to the friction pad of the drive unit detected by the load sensor and the wheel speed detected by the wheel speed sensor, the friction value is determined from the corresponding command value data. Read out the correction pressing force on the entry side and the delivery side to press the pad, respectively, and as at least one of the actual pushing force and the wheel speed, which is the clamp load on the entry side and the delivery side, increases, the delivery side The first and second drive units can be controlled to prevent the friction pads from being unevenly worn so that the correction pressing force of the first and second driving portions is larger than the correction pressing force on the entry side.

Embodiment 1
An embodiment of the present invention will be described below in detail with reference to the drawings.
FIG. 1 shows a brake system when an electric disc brake device 1 of the present invention is mounted on a vehicle. FIG. 2 is a diagram showing a schematic configuration when the electric disc brake device 1 of FIG. 1 is mounted on one wheel of a vehicle.
An electric disc brake device 1 shown in FIG. 2 is an electric brake device that uses an electric motor or the like as a driving force, and includes a disc rotor 2, a friction pad 3, a brake caliper 4, and a braking control unit 13. The

The disk rotor 2 is a disk body that rotates together with a wheel (not shown), and the friction pad 3 comes close to both surfaces of the disk body, and the rotation is braked by sliding contact.
The friction pad 3 includes a pair of friction pads 3a and a friction pad 3b that are opposed to each other with the disk rotor 2 interposed therebetween. The friction pads 3a and 3b are pressed in a direction approaching each other by the action of the brake caliper 4, and when they are in sliding contact with the disk rotor 2, the rotating kinetic energy of the disk rotor 2 is converted into heat energy by friction to brake the wheels. .

Hereinafter, the structure and configuration of the brake caliper 4 will be described with reference to FIGS.
3A is a cross-sectional view of K1-K1 of the brake caliper 4 in FIG. 3B, and FIG. 3B is a cross-sectional view of K2-K2 of the brake caliper 4 in FIG. 3A.
As shown in FIG. 3, the brake caliper 4 generally includes a caliper body 7, a bracket 6 that slidably supports the caliper body 7, and a pair of drive units 11 and 12 that are inserted into the caliper body 7. .
The bracket 6 is a U-shaped member that is attached to the non-rotating portion inside the tire wheel so as to straddle the disc rotor 2. A pair of friction pads 3 a and 3 b are arranged on the opposing surfaces of the bracket 6 so as to face each other, and the friction pads 3 a and 3 b are firmly fixed so as not to move in the rotational direction of the disk rotor 2. The bracket 6 includes a pair of slide holes 6a and 6b. When the slide bolts 8 and 8 are screwed in a state of being positioned with the mounting holes 7a and 7b provided in the caliper main body 7, the bracket 6 and the caliper main body are inserted. 7 is slidably mounted.

The caliper main body 7 includes an action part 9 and a reaction part 10 that faces the action part 9 and is provided so as to straddle the disk rotor 2. The action unit 9 includes a turn-in drive unit 11 and a turn-out drive unit 12 inside. When the turn-in side drive unit 11 and the turn-out side drive unit 12 are controlled and driven by a braking control unit 13 which will be described later, the rotation of the disc rotor 2 is braked via the action unit 9 and the reaction unit 10.
In the present embodiment, the turn-in drive unit 11 is a drive unit located on the side where the disc rotor 2 enters the caliper body 7 when it is assumed that the disc rotor 2 rotates in the direction indicated by the arrow in FIG. is there. On the contrary, the delivery side drive unit 12 is a drive unit located on the side where the disc rotor 2 exits the caliper body 7. This embodiment shows a case where the vehicle body is moving forward. Therefore, when the vehicle body moves backward, the turn-in drive unit 11 is on the turn-out side, and the turn-out drive unit 12 is on the turn-in side. In this embodiment, the turn-in drive unit 11 and the turn-out drive unit 12 are arranged in parallel along the rotation direction of the disk rotor 2. In addition, the said entrance side drive part 11 and the delivery side drive part 12 are mentioned later.

As shown in FIG. 3, the action portion 9 is divided into a cylinder body 32, a middle body 33, a body end 34, and a motor cover 35.
The cylinder body 32 has a screw hole into which a turn-in side cylinder 36 and a turn-out side cylinder 37 for incorporating a turn-in side drive unit 11 and a turn-out side drive unit 12 described later, and a fixing bolt 68 described later are screwed. 67. The feed-in side cylinder 36 and the feed-out side cylinder 37 are formed as holes with openings at both ends that extend in the left-right direction of the vehicle body, and include a stepped portion 43 having a diameter smaller than that of the opening 55. The space on the side is formed as the base diameter portion 38, and the space on the opening 55 side of the step portion 43 is formed as the enlarged diameter portion. A ring groove 39 is formed at the end of the base diameter portion 38 on the disk rotor 2 side along the inner peripheral surface. On the peripheral surface of the opening 55, a protrusion 58 that protrudes from a hole provided in the middle body 33 described later is provided.

  In the inflow side cylinder 36 and the inflow side cylinder 37, the inflow side drive unit 11 and the return side drive unit 12 shown in FIG. 4 are integrated with the bearing 41, the seal ring 45, the pressing member 48, and the dust seal 65, respectively. Assembled into. Hereinafter, members assembled in the inside of the turn-in side cylinder 36 and the turn-out side cylinder 37 will be described in detail. In addition, since the basic structure is the same as the member assembled | attached in the inflow side cylinder 36 and the inflow side cylinder 37, the case where the one inflow side drive part 11 is assembled | attached to one inflow side cylinder 36 is taken as an example. explain.

  As shown in FIG. 4A, the turn-in side drive unit 11 is roughly constituted by a piston part 21, a speed reduction mechanism 22, and an electric motor 23 as drive means. The piston portion 21 is configured as a ball screw, and includes a piston 24 having a through hole 26 penetrating in the axial direction therein and a bolt 50 projecting from the through hole 26 toward the disk rotor 2, and the piston 24. 24 and a conversion mechanism 25 configured as a ball nut screwed through the ball. That is, when the conversion mechanism 25 is rotated by driving an electric motor 23 described later, the piston 24 is advanced or retracted toward the disk rotor 2, and the piston 24 and the conversion mechanism 25 are balls of a so-called ball screw mechanism. There is a relationship between screw and ball nut. The conversion mechanism 25 is a cylindrical body having an opening at one end, and includes a screw portion 25a that is screwed with a screw cut on the outer periphery of the piston 24 on the inner peripheral wall. A round flange 42 is formed at the other closed end of the conversion mechanism 25. The end face 53 of the flange 42 is provided with a plurality of support holes 27 that are evenly arranged so as to be concentric with the center of the flange 42, and a part of a later-described reduction mechanism 22 is coupled to each of the support holes 27.

The speed reduction mechanism 22 includes a sun gear 28, a plurality of planetary gears 29, a support shaft 30 that supports the rotation of the plurality of planetary gears 29, and an outer ring gear 31. The sun gear 28 is attached to the output shaft 64 of the electric motor 23 and meshes with a plurality of planetary gears 29 arranged around the sun gear 28 to output a rotational force to the planetary gear 29.
The planetary gear 29 has a bearing 57 attached to the center of rotation, and is coupled to the support shaft 30 via the bearing 57. The support shaft 30 includes a flange 56 having a thickness larger than the shaft diameter in the middle of the shaft portion. One end of the support shaft 30 is fitted into the support hole 27 provided in the flange 42 described above, and the other end is a bearing of the planetary gear 29. The rotation of the sun gear 28 is transmitted to the conversion mechanism 25 by supporting 57. The outer ring gear 31 is fixed to a housing portion of a middle body 33 described later, and meshes with a plurality of planetary gears 29 that revolve around the sun gear 28.
An annular spacer 62 is provided closer to the electric motor 23 than the speed reduction mechanism 22. A bearing 63 is inserted into the inner circumference of the spacer 62. The bearing 63 supports the output shaft 64 of the electric motor 23. The spacer 62 is accommodated in a body end 34 to be described later.

  As the bearing 57 of the planetary gear 29, any bearing may be used as long as the output shaft 64 of the electric motor 23 coincides with the axis of the ball screw mechanism. For example, when the shaft is slightly deviated, By using an eccentric bearing or the like, the speed reduction mechanism 22 can be easily configured without changing the configuration or design.

  The electric motor 23 is a pulse motor that is connected to a motor control unit 14 to be described later by a harness 69 and whose rotation direction or rotation angle is controlled. Note that not only a rotating motor but also a linear motor, a solenoid, or the like that moves directly may be used. According to the turning-in side drive unit 11 having this configuration, when the sun gear 28 provided on the output shaft 64 is rotated by driving the electric motor 23, the plurality of planetary gears 29 provided around the sun gear 28 are rotated. And since the conversion mechanism 25 connected via the support shaft 30 rotates, the piston 24 accommodated in the conversion mechanism 25 can be driven forward and backward.

With reference to FIG.4 (b), the internal structure of the turn-in side cylinder 36 is explained in full detail.
Needle bearings 41, 41, a thrust bearing 44, a seal ring 45, a load sensor 47, a pressing member 48, and a dust seal 65 are inserted inside the introduction side cylinder 36. The needle bearings 41 and 41 are inserted in series with respect to the peripheral wall of the base diameter part 38, and hold | maintain rotatably the outer periphery of the conversion mechanism 25 inserted from the opening part 55 side. The thrust bearing 44 is inserted between the stepped portion 43 and the other end face 46 of the flange 42 of the conversion mechanism 25 to hold the conversion mechanism 25 rotatably.

  The seal ring 45 is a member that is inserted closer to the friction pad 3a than the thrust bearing 44, and is incorporated in contact with the thrust bearing 44, thereby leaking smooth oil in the bearing and dust from the outside. Prevent foreign material from entering. The load sensor 47 is a member provided closer to the disc rotor 2 than the seal ring 45. The load sensor 47 is formed of a cylindrical load cell, and detects a load (clamp load) acting on a friction pad 3a described later by four strain gauges attached to a strain body of the load cell. The detected load is output to the braking control unit 13 described later via the harness 47a. The harness 47 a extends from a harness take-out hole 52 formed on the distal end side of the base diameter portion 38 and is connected to the input portion 101 described later.

  A pressing member 48 that is pressed by the base 3c of the friction pad 3a is attached to the friction pad 3a side of the load sensor 47. The pressing member 48 is made of a ceramic or other composite material heat insulating material that prevents heat flow generated in the friction pad 3a in the load sensor 47, the piston 24, and the like, and has a screw hole 49 in the center. The pressing member 48 includes a plurality of protrusions protruding from the pressing surface 48c toward the friction pad 3a, and holds the base 3c.

The pressing member 48 and the load sensor 47 are arranged so that the bolt 50 of the piston 24 is screwed into the screw hole 49 of the pressing member 48 in a state where the conversion mechanism 25 is inserted from the opening 55 side. Fixed to the surface 51. That is, the load sensor 47 is sandwiched between the pressure receiving surface 48 a of the pressing member 48 and the tip surface 51 of the piston 24.
The dust seal 65 is a sealing member formed in an annular shape, and an inner peripheral surface of the annular ring is fitted along a groove 48b formed around the pressing member 48, and the conversion mechanism 25 is interposed from the opening 55 side. In the inserted state, the outer peripheral surface of the annular ring is fitted into the ring groove 39. As the piston 24 advances, the dust seal 65 is exposed from the opening 36a of the cylinder 36. When the dust seal 65 presses the base 3c of the friction pad 3a, foreign matter such as dust enters the cylinder 36 from the outside. To prevent. As described above, after all the members are inserted into the turn-in cylinder 36, the piston portion 21 is accommodated in the turn-in cylinder 36 from the opening 55 side.

  Referring to FIGS. 3A and 3B, a turn-in side drive portion 11 and a turn-out side drive portion 12 are respectively provided in a turn-in side cylinder 36 and a turn-out side cylinder 37 provided in the action portion 9. A state in which is incorporated will be described. When the piston portion 21 is assembled in both the cylinders 36 and 37, the speed reduction mechanism 22 is assembled through the support hole 27. The cylinder body 32 and the middle body 33 are positioned by fitting a projection 58 provided on the cylinder body 32 with a hole provided on the middle body 33. The contact surface 60 of the middle body 33 contacts the bearing 54 in the positioned state. By attaching the middle body 33, the outer ring gear 31 of the speed reduction mechanism 22 is accommodated, and the speed reduction mechanism 22 assembled to the piston part 21 and the piston part 21 is integrally supported.

  The middle body 33 has a through hole 66 through which the fixing bolt 68 passes, and the body end 34 is attached from the electric motor 23 side. The body end 34 includes a screw hole 67 and a through hole 70 that coincides with the through hole 66 formed in the middle body 33, and the fixing bolt 68 is screwed into the screw hole 67 through the through holes 70 and 66. The body end 34, the middle body 33, and the cylinder body 32 are assembled together. A motor cover 35 is attached to the electric motor 23 protruding from the body end 34.

FIG. 5 is a block diagram of a braking control unit according to the electric disc brake device 1. Note that i and o may be used as subscripts in the drawings and the specification in order to clarify the distinction between the configuration located on the entry side and the configuration located on the delivery side. The subscript i indicates a configuration located on the return side, and the subscript o indicates a configuration located on the return side.
The electric disc brake device 1 includes a storage unit 100, an input unit 101, a calculation processing unit 102, and an output unit 103, and is provided mainly on the vehicle body side and outputs various signals to the input unit 101. Brake switch 81, pedal sensor 82, wheel speed sensor 84, turn-in side load sensor 47i and turn-out side load sensor 47o that are electrically connected to input unit 101 and output load signals, and output unit 103 and turn-in side From the motor control unit 14 that is electrically connected to the electric motor 23i and the delivery-side electric motor 23o and performs drive control of the entry-side electric motor 23i and the delivery-side electric motor 23o based on an output signal from the output unit 103. Composed.

  The brake switch 81 is provided near the brake pedal, and outputs a brake signal 91 to the input unit 101 when the driver operates the brake. As the brake signal 91, for example, a so-called ON / OFF signal that is ON when the brake operation is present and OFF when the brake operation is absent is preferable. The brake switch 81 may output an ON / OFF signal by a pedal sensor 82 described later. A brake control program 200 described later is executed by the brake signal 91.

The pedal sensor 82 is a sensor that detects the amount and method of operation of the brake, and is provided in a portion where the brake pedal strokes (see FIG. 1). The pedal sensor 82 detects the depression angle (depression angle) when the brake pedal is operated and the depression strength (depression load) when the brake pedal is operated, and inputs the depression angle signal 92 and the depression force signal 93. Output to.
For example, the sensor that detects the depression angle may be any sensor that can detect the rotation angle, such as a rotary encoder. Especially when the rotary encoder is used, the angle and the angular velocity up to that angle can be detected at the same time. Speed can be detected. The sensor for detecting the stepping load can detect the stepping strength by a load sensor, a load cell or the like. In this embodiment, the pedal sensor 82 is constituted by a sensor that can output a depression angle and a depression load. Note that the signal for outputting the brake operation may be either the depression angle signal or the depression force signal.

  The wheel speed sensor 84 is a sensor that detects the rotational speed of the wheel, and includes an encoder attached to a hub or the like provided on an axle that rotates with the wheel, and a detector attached to a non-rotating portion near the hub. The encoder is an aggregate of irregularities made of magnets and metals arranged at equal intervals in the rotation direction of the hub, and changes in magnetic flux detected by the detector as a wheel speed signal 94 as an input unit. 101. As the wheel speed sensor, other known sensors may be used or combined to form a wheel speed sensor.

  The load-side load sensor 47i and the load-side load sensor 47o are load sensors that are provided in the brake caliper 4 and measure the pressing force for sliding the friction pad 3a on the disk rotor 2 as described above. The pressure generated on the pressure receiving surface 48a of the pressing member 48 that presses the pad 3a and the front end surface 51 of the piston 24 is output to the input unit 101 as a load-side load signal 95i and a load-side load signal 95o. Signals input from the sensors are output from the input unit 101 to the arithmetic processing unit 102.

The arithmetic processing unit 102 is configured by hardware such as a CPU, a ROM, and a RAM. For example, the processing program stored in the ROM and the return-side command value data 98i and the return-side command value data 98o stored in the storage unit 100 are used. Referring to Fig. 5, the calculation process of the pressing force of both electric motors 23i and 23o to be controlled is executed using the RAM.
The storage unit 100 is, for example, a storage medium such as a ROM, and stores the entry side command value data 98i and the delivery side command value data 98o necessary for the arithmetic processing by the arithmetic processing unit 102.
Note that the storage unit 100 may be included in the arithmetic processing unit 102.

FIG. 7 shows the command value data 98i and the command value data 98o stored in the storage unit 100. The wheel speed S based on the wheel speed signal 94, and the rotation speed based on the turn-in load signal 95i and the return load signal 95o. Entry side actual pressing force Fin as the inlet side clamp load, traction side actual pressing force Fout as the outlet side clamp load, and inlet side corrected pressing force P * in and rotation as the inlet side input load The relationship with the delivery side corrected pressing force P * out as the delivery side input load is shown.
The command value data 98i is data for obtaining the corrected pressing force P * in according to the wheel speed S and the actual pressing force Fin on the turn-in side. The command value data 98o is data for obtaining the correction pressure P * out on the delivery side from the wheel speed S and the actual pressure Fout on the delivery side.
The command value data 98i and the command value data 98o indicate that, as at least one of the wheel speed S and the actual pressing force Fin and Fout increases, the correction pressure P * out on the delivery side becomes the correction pressure P * on the circulation side. It is set so that the increasing rate of the correction pressing force is larger than in.
Further, as shown in FIG. 8A, the command value data 98i and the command value data 98o indicate whether or not the surface pressure distribution generated in the friction pad 3 is controlled or not when the wheel speed S and the actual pressing forces Fin and Fout are small. Regardless of the change, regardless of the wheel speed S and the actual pressing force Fin or Fout, the return side input load is larger than the return side input load when at least one of them is larger than a preset value (threshold). You may set so that it becomes.
The return side command value data 98i and the return side command value data 98o are corrected according to either the wheel speed S or the actual pressing force Fin or Fout detected on the return side or the return side. Pressing force P * in and P * out are output, and the correction pressure P * out on the delivery side is set so that the increasing rate of the correction pressing force is greater than the correction pressing force P * in on the entry side. May be.

The motor control unit 14 is interposed between the electric motors 23 i and 23 o which are drive sources provided in the brake caliper 4 and the braking control unit 13, and supplies the electric motors 23 i and 23 o output from the braking control unit 13. The target pressing force signals 96i and 96o are converted into a return-side drive signal 97i and a return-side drive signal 97o suitable for the electric motors 23i and 23o and output.
For example, when the electric motor 23 is a stepping motor, the rotation of the motor is performed according to the number of pulse signals sent as a control signal. Therefore, when the signal output from the braking control unit 13 is a current, it is converted into a pulse signal or the like. To do. The motor control unit 14 may be configured by a motor driver, and the function thereof may be incorporated in the braking control unit 13.

A control method by the electric disc brake device 1 having the above configuration will be described with reference to the flowchart of FIG.
When a brake operation is performed while the vehicle is running, a brake signal 91 output from the brake switch 81 is output via the input unit 101, and the arithmetic processing unit 102 starts control processing based on the braking control program 200 (S1). ).

  In step 1, based on the start of the control process, the arithmetic processing unit 102 detects the wheel speed signal 94, the depression angle signal 92, and the depression force signal 93 input via the input unit 101 (S2).

  Based on the depression angle signal 92, the depression force signal 93, and the wheel speed signal 94 detected in step 2, the arithmetic processing unit 102 applies to the disc rotor 2 so as to approach the target braking force according to the operation of the brake pedal by the driver. The target pressing forces Pin and Pout of the friction pad 3a are calculated, and the calculation results are output to the output unit 103 as target pressing force signals 96i and 96o (S3).

  The output unit 103 outputs the target pressing force signals 96i and 96o output from the arithmetic processing unit 102 in step 3 to the motor control unit 14, and the motor control unit 14 outputs the corresponding turn-in side drive signal 97i and the return side drive. The signal is converted into the signal 97o and output to the electric motors 23i and 23o (S4).

  The electric motors 23i and 23o cause the pistons 24i and 24o to protrude by the driving force according to the turn-in side drive signal 97i and the turn-out side drive signal 97o output from the output unit 103 in Step 4, and the friction pads 3a. Is pressed against the disc rotor 2 (S5).

  When the pistons 24i and 24o protrude in step 5 and the pressing member 48 comes into contact with the base 3c of the friction pad 3a, the turn-in side load sensor 47i and the turn-out side load sensor 47o provided between the pistons 24i and 24o The inflow side actual pressing force Fin and the infeed side actual pressing force Fout are detected, and the ingress side actual pressing force Fin and the unwinding side actual pressing force Fout are used as the ingress load signal 95i and the unfolding load signal 95o. It outputs to the input part 101 of the brake control part 13 (S6). In the initial state of the brake operation, the actual pressing forces Fin and Fout detected by the turn-in side load sensor 47i and the turn-out side load sensor 47o are not corrected at the time of high load in FIG. A surface pressure distribution as shown in FIG.

In step 6, when the turning load signal 95 i and the turning load signal 95 o are input via the input unit 101, the arithmetic processing unit 102 inputs the input turning side actual pressing force Fin and the turning side actual pressing force. Based on Fout (round-in load signal 95i and round-out load signal 95o) and wheel speed S (wheel speed signal 94) output from the wheel speed sensor 84, round-in side command value data 98i stored in the storage unit 100. And the return-side corrected pressing force P * in and the return-side corrected pressing force P * out are calculated and output to the output unit 103 (S7).
For example, as a control example, if the braking is performed at a high load from high speed running, the actual pressing forces Fin and Fout detected on the entrance side and the exit side are large. For the correction pressing force P * out, refer to the turn-in side command value data 98i and the turn-out side command value data 98o. Is output as a return-side correction pressing force P * in and a rotation-side correction pressing force P * out.

  In step 7, the output unit 103 outputs correction pressing force signals 96 * i and 96 * o based on the return side correction pressing force P * in and the output side correction pressing force P * out to the motor control unit 14. To do.

The motor control unit 14 converts the correction pressing force signals 96 * i and 96 * o into the return side correction drive signal 97 * i and the return side correction drive signal 97 * o, respectively, and outputs them to the electric motors 23i and 23o. (S8). The electric motors 23i and 23o operate so as to have the correction pressing forces P * in and P * out with respect to the friction pad 3a based on the correction pressure P * in and the correction pressure P * out. (S9).
By repeating the above steps S6 to S9, the control is repeated so that the surface pressure distribution acting on the friction pad 3 becomes uniform.

  As described above, the electric motor 23 is based on the corrected pressing forces P * in and P * out based on the command value data 98i and 98o and the actual pressing forces Fin and Fout generated on the turn-in side and the turn-out side. The braking force is controlled such that the distribution of the surface pressure acting on the disc rotor 2 is uniform according to the driver's braking operation force. As a result, uneven wear of the friction pad can be prevented by making the surface pressure distribution of the friction pad 3 uniform.

Embodiment 2
FIG. 10 (a) shows another embodiment according to the present invention. In addition, about the member of the same structure as Embodiment 1, a code | symbol is abbreviate | omitted suitably. The present embodiment is different from the electric disk brake device 1 having the same configuration as in the first embodiment in that the load sensor 47 is provided not in the action portion 9 but in the reaction portion 10. Specifically, the load sensor 77 in the present embodiment is provided on the reaction portion 10 side. In this state, when the pistons 24i and 24o of the action portion 9 project and the pressing member 48 presses the base 3c of the friction pad 3a, the friction pad 3a comes into sliding contact with the disk rotor 2. At the same time, the caliper body 7 slides along the slide holes 6 a and 6 b of the bracket 6 by the reaction force, and the friction pad 3 b on the reaction portion 10 side is pressed against the disc rotor 2. Thereby, the same operation as the load sensors 47i and 47o provided to the pistons 24i and 24o in the first embodiment can be obtained.

That is, the second embodiment is characterized in that the actual pressing pressures Fin and Fout are not detected by the action portion 9 side, but the actual pressing forces Fin and Fout are measured on the reaction portion 10 side. According to this method, the load sensor 77 can be easily installed on the caliper main body 7 and, for example, when there are a plurality of pistons that press the friction pad 3a, the plurality of load sensors 47 are not used. One load sensor 77 can control the pressing force of each piston.
The actual pressing forces Fin and Fout can be detected with high accuracy by providing a plurality of load sensors 77 at positions corresponding to the axes of the pistons 24i and 24o on the reaction portion 10 side instead of having a single configuration. be able to.

Embodiment 3
Further, as shown in FIG. 10B, more accurate control can be performed by detecting the load in both directions by combining the load sensors 47i and 47o with the load sensor 77. For example, as described above, the friction pad 3a is brought into sliding contact with the disk rotor 2 by the protrusions of the pistons 24i and 24o of the action portion 9, so that the caliper body 7 slides by the reaction force along the slide holes 6a and 6b of the bracket 6. The friction pad 3 b on the reaction portion 10 side is in sliding contact with the disk rotor 2.

  That is, since the pressing force acting on the friction pad 3b depends on the pressing force acting on the friction pad 3a, in order to know the exact pressing force acting on the friction pads 3a, 3b, the action portion 9 and By providing the reaction sensor 10 with the load sensor 47 and the load sensor 77, it is possible to perform control with high accuracy.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

1 is a conceptual diagram of an electric disc brake device for a vehicle according to the present invention. 1 is a perspective view of an electric disc brake device in a part of a vehicle according to the present invention. Sectional drawing of the electrically driven brake caliper which concerns on Embodiment 1 of this invention. The block diagram of the electric brake caliper which concerns on Embodiment 1 of this invention. The block diagram of the brake control part which concerns on Embodiment 1 of this invention. The flowchart of the braking control program which concerns on Embodiment 1 of this invention. The command value data graph which the memory | storage part which concerns on Embodiment 1 of this invention memorize | stores. FIG. 6 is a distribution diagram of surface pressure acting on a friction pad depending on whether correction is performed according to the first embodiment of the present invention. The general surface pressure distribution figure which acts on the friction pad which concerns on this invention. The block diagram of the load sensor which concerns on other embodiment of this invention.

Explanation of symbols

1 electric disc brake device, 2 disc rotor, 3 friction pads,
4 brake caliper, 11 turn-in drive section, 12 turn-out drive section, 13 brake control section, 14 motor control section, 21 piston section, 22 reduction mechanism, 23 electric motor,
47 Load sensor, 81 Brake switch, 82 Pedal sensor,
84 Wheel speed sensor.

Claims (1)

A friction pad that is slidably contacted with the disk rotor from each of the action part and the reaction part of the caliper body;
A pressing member that presses the friction pad;
Drive means comprising at least first and second drive portions provided on the action portion side and disposed on each of the turn-in side and the turn-out side of the disk rotor that generates a pressing force on the pressing member;
A control unit for controlling the driving means;
An electric disc brake device having storage means,
A load sensor capable of detecting the actual pressing force on the turn-in side and the turn-out side applied to the friction pad of the drive unit;
A wheel speed sensor for detecting the wheel speed,
The storage means stores command value data for obtaining a correction pressing force necessary for adding to a preset friction pad,
The command value data indicates that as at least one of the wheel speed and the actual pressing force becomes larger, the correction pressing force on the delivery side that presses the pressing member increases the correction pressing force than the correction pressing force on the entry side. The relationship between the wheel speed, the actual pressing force, and the correction pressing force is set corresponding to the inflow side and the outflow side so that the rate increases.
The control unit includes a wheel speed detected by a wheel speed sensor, an actual pressing force on a turn-in side as a clamp load on a turn-in side detected by the load sensor, and a delivery side as a clamp load on a delivery side. The actual pressing force is referred to the command value data stored in the storage means, and as at least one of the wheel speed and the actual pressing force increases, the correction pressing force on the delivery side that presses the pressing member is increased. However, the electric disc brake device controls the first and second drive units so that the increasing rate of the correction pressing force is larger than the correction pressing force on the entry side .

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