JP2015137667A - Electric brake device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric brake device capable of generating a brake force even when electrical failure occurs.SOLUTION: An electric brake device includes: a rotary shaft 14 in which rotation of an electric motor 4 is inputted; an outer ring member 15 supported movably in an axial direction; a planetary roller mechanism 16 for converting the rotation of the rotary shaft 14 into axial direction movement of the outer ring member 15; and a friction pad 3 arranged in an axial direction front side of the outer ring member 15. By the outer ring member 15 pressing the friction pad 3, the friction pad 3 is pressed against a brake disk 1 integrally rotating with a wheel. A pressing mechanism 6 is provided for pressing the rotary shaft 14 to the axial direction front side by an operational force of an operator, and when the rotary shaft 14 is pressed by the pressing mechanism 6, the rotary shaft 14 and the outer ring member 15 integrally move to the axial direction front side and press the friction pad 3.

Description

  The present invention relates to an electric brake device using an electric motor as a drive source.

  Conventionally, as a vehicle brake device, a hydraulic brake device using a hydraulic pressure as a drive source has been often adopted. However, the hydraulic brake device uses a brake oil, and thus has a high environmental load, and includes ABS, ESC, brake assist, and the like. It is difficult to further enhance the functions. Therefore, an electric brake device has attracted attention as a means for realizing further enhancement of the function of the brake device and reduction of environmental load (for example, Patent Document 1). In general, an electric brake device converts rotation of an electric motor into axial movement of a friction pad, and presses the friction pad against a brake disk to generate a braking force.

JP 2012-87889 A

  By the way, the electric brake device as disclosed in Patent Document 1 is such that when an electric failure such as an abnormal decrease in the charge amount of a battery that supplies power to the electric motor, a sensor failure, or disconnection of an electric wiring occurs, May not work. In this case, since the friction pad cannot be pressed against the brake disc, it may not be possible to generate a braking force on the wheel that rotates integrally with the brake disc.

  The problem to be solved by the present invention is to provide an electric brake device capable of generating a braking force even when an electrical failure occurs.

In order to solve the above problems, the inventor of the present application employs the following configuration in the electric brake device.
An electric motor;
A rotating shaft to which the rotation of the electric motor is input;
A linear motion member supported so as to be movable in the axial direction;
A motion conversion mechanism that converts rotation of the rotary shaft into axial movement of the linear motion member;
A friction pad disposed in the axially forward direction of the linear motion member,
In the electric brake device that presses the friction pad against a brake disc that rotates integrally with a wheel by the linear motion member pressing the friction pad,
A pressing mechanism for pressing the rotating shaft forward in the axial direction by a driver's operating force is provided,
The electric brake device according to claim 1, wherein when the rotary shaft is pressed by the pressing mechanism, the rotary shaft and the linear motion member integrally move forward in the axial direction to press the friction pad.

  In this way, even when the electric motor is not operating, the rotating shaft is pressed forward in the axial direction by the driver's operating force, and the rotating shaft and the linear motion member are moved together in the axial direction to cause friction. The pad can be pressed against the brake disc. Therefore, it is possible to generate a braking force even when an electrical failure occurs. Also, when the rotating shaft is pressed forward in the axial direction, the rotating shaft does not rotate and moves axially forward together with the linear motion member, so that the rotation of the rotating shaft is obstructed for some reason However, it is possible to generate a braking force.

The linear motion member is an outer ring member arranged so as to surround the rotation shaft,
The motion conversion mechanism is provided on the inner periphery of the outer ring member, a plurality of planetary rollers that circumscribe the rotating shaft and at the same time inscribed in the outer ring member, a carrier that supports the planetary rollers so as to rotate and revolve. A planetary roller mechanism having a spiral ridge and a circumferential groove or a spiral groove provided on the outer periphery of the planetary roller so as to engage with the spiral ridge,
A flange for supporting the carrier from the rear side in the axial direction may be provided on the outer periphery of the rotating shaft.

  In this case, the planetary roller mechanism has a higher force increase ratio (ratio of axial thrust of the linear motion member to rotational torque input to the rotation shaft) than other motion conversion mechanisms such as a feed screw mechanism. The size of the electric brake device can be reduced. When the rotary shaft is pressed by the pressing mechanism and moves forward in the axial direction, the flange provided on the outer periphery of the rotary shaft pushes the carrier forward in the axial direction, so that the planetary roller supported by the carrier also has a shaft. The outer ring member that moves forward in the direction and engages the planetary roller also moves forward in the axial direction. As a result, when the rotating shaft is pressed by the pressing mechanism and moves forward in the axial direction, the outer ring member that is a linear motion member moves forward in the axial direction integrally with the rotating shaft.

The following configuration can be added to the electric brake device.
A brake pedal supported swingably and operated by the driver's foot;
A wire connector portion that is supported so as to be able to swing independently of the brake pedal, and to which the other end of a wire cable having one end connected to the pressing mechanism is connected;
A connection state in which the brake pedal and the wire connector part are connected so that the brake pedal and the wire connector part swing together, and an operating force of a driver acting on the brake pedal is the wire connector part. And a clutch mechanism for switching between a disconnected state in which the brake pedal and the wire connector portion are disconnected from each other so as to cut off the transmission.

  In this way, when an electrical failure occurs, the driver can operate the brake pedal by switching the clutch mechanism from the disconnected state to the connected state, as in the case where no electrical failure has occurred. It is possible to generate a braking force and excellent operability when an electrical failure occurs.

  The clutch mechanism is preferably a reverse-acting electromagnetic clutch configured to be in the disconnected state when energized and in the connected state when energization is stopped.

  In this way, when the energization of the clutch mechanism is stopped, the clutch mechanism is in a connected state, so that it is possible to avoid a situation in which no braking force can be generated even when the electric brake device loses power. High safety can be ensured.

Moreover, the following configuration can be added to the electric brake device.
A battery sensor for detecting a filling amount of a battery for supplying electric power to the electric motor;
A control unit that controls the clutch mechanism based on a detection signal of the battery sensor;
The control unit controls the clutch mechanism to switch from the disengaged state to the connected state when the battery sensor detects that the charge amount of the battery is below a preset threshold value. It is configured.

  In this way, the clutch mechanism is engaged when the charge amount of the battery falls below the threshold value, so that a situation in which the braking force cannot be generated when the charge amount of the battery decreases can be avoided.

  It is also possible to connect the other end of the wire cable having one end connected to the pressing mechanism to a parking brake lever operated by the driver's hand. Thereby, the mechanism of the electric brake device can be used as a parking brake.

As the pressing mechanism, for example,
A cam member supported so as to be rotatable about an axis perpendicular to the axial direction of the rotation shaft, and having a shape for pressing the rotation shaft forward in the axial direction according to the rotation angle;
One having a wire lever that rotates integrally with the cam member and to which one end of the wire cable is connected may be employed.

As the pressing mechanism, for example,
A linear motion disk disposed behind the rotating shaft in the axial direction and supported so as to be movable in the axial direction in a state of being prevented from rotating;
A rotating disk that is arranged facing the axially rearward of the linearly-moving disk and is rotatably supported in a state where movement in the axially rearward direction is restricted;
A ball incorporated between the inclined groove formed on the surface of the linear disk facing the rotating disk and the inclined groove formed on the surface of the rotating disk facing the linear disk;
A ball ramp mechanism that rotates integrally with the rotating disk and has a wire lever to which one end of the wire cable is connected can be employed.

  In the electric brake device of the present invention, even when the electric motor is not operating, the rotating shaft is pressed forward in the axial direction by the operating force of the driver, and the rotating shaft and the linear motion member are integrally moved forward in the axial direction. Thus, it is possible to press the friction pad against the brake disc. Therefore, it is possible to generate a braking force even when an electrical failure occurs.

The figure which looked at the electric brake equipment of a 1st embodiment of this invention from the diameter direction inside of a brake disc Sectional view along the line II-II in FIG. Sectional view along line III-III in FIG. Enlarged sectional view of the electric brake device shown in FIG. FIG. 4 is an enlarged sectional view in the vicinity of the speed reduction mechanism of FIG. FIG. 4 is an enlarged sectional view in the vicinity of the planetary roller mechanism of FIG. Sectional drawing along the VII-VII line of FIG. FIG. 6 is an enlarged sectional view in the vicinity of the pressing mechanism. The block diagram which shows the control system of the electric brake device shown in FIG. FIG. 9 is a flowchart showing a control example by the brake control device shown in FIG. The flowchart which shows the other example of control by the brake control apparatus shown in FIG. The expanded sectional view which shows the other example of the press mechanism shown in FIG. Sectional view along line XIII-XIII in FIG. (A) is sectional drawing in alignment with the XIV-XIV line | wire of FIG. 13, (b) is a figure which shows the state which the rotation disc rotated from the state shown to (a), and the space | interval of both discs expanded. The figure which shows the modification of the press mechanism shown in FIG. The figure which shows the other example of the clutch mechanism shown in FIG. The figure which shows the state which made the clutch mechanism shown in FIG. 16 the connection state. The figure which looked at the electric brake device of 2nd Embodiment of this invention from the radial inside of the brake disc

  1 and 2 show an electric brake device according to a first embodiment of the present invention. This electric brake device includes a brake disc 1 that rotates integrally with a wheel, a pair of friction pads 2 and 3 that face each other in the axial direction with the brake disc 1 interposed therebetween, and an electric motor for moving the friction pads 2 and 3. 4 and presses the friction pads 2 and 3 against the brake disc 1 with the power transmitted from the electric motor 4 to generate a braking force. In addition, this electric brake device enables generation of a braking force even in a state where the electric motor 4 does not operate due to an electrical failure, so that the wire cable 5 provided to be pulled by the driver's operating force; And a pressing mechanism 6 connected to one end of the wire cable 5.

  The electric brake device includes a caliper body 10 having a shape in which a pair of facing portions 7 and 8 that face each other in the axial direction with the brake disc 1 interposed therebetween are connected by a bridge 9 positioned on the outer diameter side of the brake disc 1. The friction pad 2 is disposed between one facing portion 7 of the caliper body 10 and the brake disk 1, and the friction pad 3 is disposed between the other facing portion 8 and the brake disk 1. The friction pads 2 and 3 are supported by pad pins (not shown) attached to the caliper body 10 so as to be movable in the axial direction of the brake disc 1.

  As shown in FIG. 3, the caliper body 10 is moved in the axial direction of the brake disc 1 by a pair of slide pins 13 attached to a caliper bracket 12 fixed to a knuckle (not shown) that supports a wheel by bolts 11. Supported as possible. Accordingly, when the friction pad 3 shown in FIG. 2 moves forward in the axial direction and is pressed against the brake disc 1, the caliper body 10 moves rearward in the axial direction due to the reaction force received from the brake disc 1, and this caliper The friction pad 2 on the opposite side is also pressed against the brake disk 1 by the movement of the body 10.

  As shown in FIG. 4, one opposing portion 8 of the caliper body 10 includes a cylindrical caliper housing 8A that is open at both front and rear ends in the axial direction, and a right angle with respect to the axial direction from the end portion on the rear side in the axial direction of the caliper housing 8A. A caliper flange 8B extending in a specific direction (a direction parallel to the brake disc 1).

  The caliper housing 8A incorporates a rotating shaft 14, an outer ring member 15 disposed so as to surround the rotating shaft 14, and a planetary roller mechanism 16 that converts rotation of the rotating shaft 14 into axial movement of the outer ring member 15. ing. The friction pad 3 is disposed in front of the outer ring member 15 in the axial direction.

  The electric motor 4 is attached to the caliper flange 8B. Between the electric motor 4 and the rotating shaft 14, a speed reduction mechanism 17 that decelerates and transmits the rotation of the electric motor 4 to the rotating shaft 14 is provided. The speed reduction mechanism 17 is accommodated in a cover 18 provided so as to cover the end opening on the rear side in the axial direction of the caliper housing 8A and the side surface of the caliper flange 8B.

  The electric motor 4 includes a rotor 19, a stator 20, and a motor housing 21. The motor housing 21 is fixed to the caliper flange 8B. The rotor 19 includes a rotor shaft 19A that is rotatably supported by a bearing 22 attached to the motor housing 21, and a rotor core 19B that is fixed to the outer periphery of the rotor shaft 19A. The stator 20 includes a stator core 20A fixed to the inner periphery of the motor housing 21 and an electromagnetic coil 20B wound around the stator core 20A. When the electromagnetic coil 20B is energized, a rotational force is generated in the rotor core 19B by the electromagnetic force acting between the stator core 20A and the rotor core 19B, and the rotor shaft 19A rotates integrally with the rotor core 19B.

  As shown in FIG. 5, the reduction mechanism 17 further reduces the rotation of the first gear train 23 that transmits the rotation of the rotor shaft 19 </ b> A of the electric motor 4 at a reduced speed, and the rotation transmitted from the first gear train 23. And a third gear train 25 for further reducing the speed of rotation transmitted from the second gear train 24 and transmitting it to the rotating shaft 14. The rotation of the electric motor 4 is sequentially decelerated and transmitted through the plurality of gear trains 23, 24, and 25 and is input to the rotary shaft 14 (see FIG. 4).

  The speed reduction mechanism 17 includes a parking lock state in which rotation of a gear 26 (here, an output side gear of the second gear train 24) included in the plurality of gear trains 23, 24, and 25 constituting the speed reduction mechanism 17 is prevented. In addition, a lock mechanism 27 that can switch between an unlocked state that allows the rotation of the gear 26 is provided. The lock mechanism 27 includes a plurality of locking holes 28 provided at equal intervals in the circumferential direction on the side surface of the gear 26, a lock pin 29 provided so as to be detachable from the locking holes 28, and the lock pin 29. And a lock actuator 30 for moving the actuator.

  When the friction pad 3 is pressed against the brake disc 1 by the operation of the electric motor 4, the lock mechanism 27 moves the lock pin 29 by the lock actuator 30 to the locking hole 28 on the side surface of the gear 26. By engaging the lock pin 29, it is possible to temporarily prevent the gear 26 from rotating in the direction in which the pressing force of the friction pad 3 against the brake disk 1 is released.

  As shown in FIG. 6, the planetary roller mechanism 16 includes a plurality of planetary rollers 31 that circumscribe the rotating shaft 14 and also inscribe the outer ring member 15, and a carrier 32 that supports the planetary rollers 31 so as to rotate and revolve. The outer ring member 15 includes a spiral protrusion 33 provided on the inner periphery of the outer ring member 15 and a circumferential groove 34 provided on the outer periphery of the planetary roller 31 so as to engage with the spiral protrusion 33.

  As shown in FIG. 7, the plurality of planetary rollers 31 are arranged at equal intervals in the circumferential direction. Each planetary roller 31 is in rolling contact with the outer periphery of the rotating shaft 14 and the inner periphery of the outer ring member 15. The contact portion of the rotating shaft 14 with respect to the planetary roller 31 is a cylindrical surface. When the rotating shaft 14 rotates, the planetary roller 31 revolves around the rotating shaft 14 while rotating around the roller shaft. That is, the planetary roller 31 rotates by the rotational force received from the outer periphery of the rotating shaft 14, and accordingly, the planetary roller 31 rolls around the inner periphery of the outer ring member 15 and revolves.

  The spiral protrusion 33 on the inner periphery of the outer ring member 15 is a spiral protrusion extending obliquely with respect to the circumferential direction. On the other hand, the circumferential groove 34 on the outer periphery of the planetary roller 31 is a groove extending parallel to the circumferential direction. In this embodiment, the circumferential groove 34 having a lead angle of 0 degree is provided on the outer periphery of the planetary roller 31. However, instead of the circumferential groove 34, a spiral groove having a lead angle different from that of the spiral protrusion 33 may be provided. Good.

  As shown in FIG. 6, the outer ring member 15 is supported on the inner surface of the caliper housing 8A so as to be movable in the axial direction. The contact portion of the inner surface of the caliper housing 8A with the outer ring member 15 is a cylindrical surface. The outer ring member 15 has a concave portion 36 that engages with a convex portion 35 formed on the back surface of the friction pad 3, and is prevented from rotating with respect to the caliper housing 8 </ b> A by the engagement of the convex portion 35 and the concave portion 36. (See FIG. 4).

  The carrier 32 extends in the axial direction between a pair of carrier plates 37 and 38 that face each other in the axial direction with the planetary roller 31 therebetween, and connects the carrier plates 37 and 38 to each other in the circumferential direction. It has the connection part 39 and the roller shaft 40 which supports each planetary roller 31 so that rotation is possible. Each of the carrier plates 37 and 38 is formed in an annular shape that penetrates the rotating shaft 14, and a sliding bearing 41 that is in sliding contact with the outer periphery of the rotating shaft 14 is mounted on the inner periphery thereof.

  Both end portions of each roller shaft 40 are supported so as to be movable in the radial direction of the outer ring member 15 by elongated holes 42 formed in the pair of carrier plates 37 and 38, respectively. Further, elastic rings 43 are stretched around both ends of each roller shaft 40 so as to circumscribe the roller shafts 40 of all the planetary rollers 31 arranged at intervals in the circumferential direction. The elastic ring 43 prevents each planetary roller 31 from slipping between the planetary roller 31 and the rotating shaft 14 by pressing each planetary roller 31 against the outer periphery of the rotating shaft 14.

  An annular bearing support member 44 is provided in the caliper housing 8 </ b> A at a position separated rearward in the axial direction with respect to the outer ring member 15. A radial bearing 45 that rotatably supports the rotary shaft 14 is incorporated in the inner periphery of the bearing support member 44. The fit between the inner periphery of the radial bearing 45 and the outer periphery of the rotary shaft 14 is a clearance fit or an intermediate fit. The bearing support member 44 is restricted from moving rearward in the axial direction by a stopper ring 46 attached to the inner periphery of the axially rear end of the caliper housing 8A.

  Between each planetary roller 31 and the carrier plate 38 on the rear side in the axial direction, a thrust bearing 47 that supports the planetary roller 31 so as to rotate is incorporated. A thrust plate 48 that revolves integrally with the carrier plate 38 and a thrust bearing 49 that supports the thrust plate 48 so as to revolve between the carrier plate 38 and the bearing support member 44 on the rear side in the axial direction of the planetary roller 31. And are incorporated.

  The bearing support member 44 supports the carrier plate 38 in the axial direction via the thrust plate 48 and the thrust bearing 49, thereby restricting movement of the carrier 32 in the rearward direction in the axial direction. The carrier plate 37 on the front side in the axial direction is restricted from moving forward in the axial direction by a retaining ring 50 attached to the front end in the axial direction of the rotary shaft 14. Therefore, the movement of the carrier 32 in both the axial front and the rear in the axial direction is restricted, and the planetary roller 31 held by the carrier 32 is also restricted in the axial movement.

  A flange 51 that supports the carrier 32 from the rear side in the axial direction is formed on the outer periphery of the rotating shaft 14. The flange 51 is disposed so as to face the rearward in the axial direction of the carrier plate 38 on the rear side in the axial direction. When the rotary shaft 14 moves forward in the axial direction, the flange 51 moves the carrier plate 38 forward in the axial direction. It is designed to push and move. The flange 51 may be formed so as to have a seamless integrated structure with the rotary shaft 14, or may be formed by fixing another member on the outer periphery of the rotary shaft 14. A thrust bearing may be incorporated between the flange 51 and the carrier plate 38. Further, the flange portion 51 may support the carrier 32 from the axial rear side via the thrust plate 48, and support the carrier 32 from the axial rear side via the bearing support member 44, the thrust bearing 49, or the like. It is also possible to configure so as to.

  A seal cover 52 that closes the opening at the front end of the outer ring member 15 in the axial direction is attached to the end of the outer ring member 15 on the front side in the axial direction. The seal cover 52 prevents foreign matter from entering the outer ring member 15. In addition, one end of a cylindrical bellows 53 formed so as to be expandable and contractable in the axial direction is fixed to an end portion on the axially front side of the outer ring member 15, and the other end of the bellows 53 is an opening on the axially front side of the caliper housing 8A. It is fixed to the edge. Bellows 53 prevents foreign matter from entering between the sliding surfaces of outer ring member 15 and caliper housing 8A.

  When the planetary roller mechanism 16 rotates the electric motor 4, the rotation of the electric motor 4 is input to the rotary shaft 14 via the speed reduction mechanism 17, and the planetary roller 31 revolves while rotating (see FIG. 4). At this time, the outer ring member 15 and the planetary roller 31 move relative to each other in the axial direction due to the difference in the lead angle between the spiral ridge 33 and the circumferential groove 34, but the planetary roller 31 is restricted from moving in the axial direction together with the carrier 32. Therefore, the planetary roller 31 does not move in the axial direction, and the outer ring member 15 moves in the axial direction. Here, when the rotation in the direction in which the outer ring member 15 moves forward in the axial direction is input from the electric motor 4 to the rotation shaft 14, the outer ring member 15 presses the friction pad 3, whereby the friction pad shown in FIG. 2 and 3 are pressed against the brake disc 1, and a braking force is applied to the wheels that rotate integrally with the brake disc 1. When the rotation in the direction in which the outer ring member 15 moves rearward in the axial direction is input from the electric motor 4 to the rotary shaft 14, the friction pads 2 and 3 shown in FIG. The braking force is released.

  As shown in FIG. 8, the pressing mechanism 6 includes a slide member 54 provided to be movable in the axial direction so as to face the rear end in the axial direction of the rotating shaft 14, and an axis perpendicular to the axial direction of the rotating shaft 14. A wire lever 57 to which a cam member 55 rotatably supported, a link member 56 incorporated between the slide member 54 and the cam member 55, and a wire end fitting 5a provided at one end of the wire cable 5 are connected. And have. One end of the wire lever 57 is connected to the cam member 55 so that when the wire cable 5 connected to the other end of the wire lever 57 is pulled, the wire lever 57 and the cam member 55 rotate together. It has become.

  The slide member 54 is slidably supported by an inner surface of a guide hole 58 provided in the cover 18 and extending in the axial direction. A concave portion 59 that receives one end of the link member 56 is formed on the end surface on the rear side in the axial direction of the slide member 54. A cam surface 60 is formed on the outer periphery of the cam member 55. The cam surface 60 has such a shape that when the cam member 55 is rotated by a pulling operation of the wire cable 5, the slide member 54 is pressed forward in the axial direction via the link member 56 according to the rotation angle. Is formed. The wire lever 57 is attached with a return spring 61 that urges the wire lever 57 in a direction opposite to the direction in which the wire lever 57 is rotated by pulling the wire cable 5 (see FIG. 2).

  In the pressing mechanism 6, when the wire cable 5 shown in FIG. 8 is pulled, the cam member 55 is rotated by the tensile force acting on the wire cable 5, and the cam surface 60 is moved according to the rotation angle of the cam member 55. The slide member 54 is pushed and moved forward in the axial direction via the link member 56, and as a result, the end surface on the front side in the axial direction of the slide member 54 presses the rotary shaft 14 forward in the axial direction.

  As shown in FIG. 1, a brake pedal 62 operated by a driver's foot includes a wire connector portion 63 to which a wire end fitting 5b provided at an end portion of the wire cable 5 is connected, and a clutch mechanism 64. It is attached. The brake pedal 62 is supported so as to be swingable about a fulcrum shaft 65. A stroke sensor 66 (see FIG. 9) for detecting the depression amount of the brake pedal 62 is attached to the brake pedal 62. The wire connector portion 63 is supported so as to be swingable so as to have a swing center at the same position as the fulcrum shaft 65 of the brake pedal 62. Here, the wire connector portion 63 can swing independently of the brake pedal 62 so that the brake pedal 62 can swing away from the wire connector portion 63.

  The clutch mechanism 64 is connected to connect the brake pedal 62 and the wire connector portion 63 so that the brake pedal 62 and the wire connector portion 63 swing together when the driver depresses the brake pedal 62, and The brake pedal 62 and the wire connector portion 63 are configured to be switchable between a disconnected state and a disconnection state so as to block transmission of the driver's operating force acting on the brake pedal 62 to the wire connector portion 63. Here, the clutch mechanism 64 is a reverse operation type electromagnetic clutch configured to be disconnected when energized and to be connected when energization is stopped.

  The electric motor 4 and the clutch mechanism 64 of this electric brake device are controlled by a brake control unit 70 shown in FIG. On the input side of the brake control unit 70, a stroke sensor 66 that detects the operation amount of the brake pedal 62, a pressing force sensor 67 that detects the pressing force with which the friction pad 3 presses the brake disk 1, and the electric motor 4 A battery sensor 69 that detects the filling amount of the battery 68 that supplies electric power is connected.

  As the pressing force sensor 67, for example, when the brake disc 1 is pressed with the friction pad 3, the friction pad 3 is deformed based on the deflection amount or the displacement amount of the bearing support member 44 that generates a deflection in accordance with the magnitude of the pressing force. Those that detect the pressing force, and those that detect the pressing force of the friction pad 3 based on the pressure acting between the thrust bearing 49 and the bearing support member 44 when the brake disk 1 is pressed by the friction pad 3 are adopted. can do.

  The electric motor 4, the clutch mechanism 64, the battery warning lamp 71, and the brake warning lamp 72 are connected to the output side of the brake control unit 70. The battery warning light 71 is an in-vehicle device provided in the driver's seat to notify the driver of an abnormality in the insufficient charge amount of the battery 68, and the brake warning light 72 indicates an abnormality such as a malfunction of the brake to the driver. It is a vehicle-mounted device provided in the driver's seat for notification.

  Next, a control example of the electric motor 4 and the clutch mechanism 64 by the brake control unit 70 will be described based on FIG. This control is a control that enables generation of a braking force when the electric motor 4 stops operating due to an abnormal decrease in the charge amount of the battery 68 that supplies power to the electric motor 4.

The brake control unit 70 first confirms the ON / OFF state of the clutch mechanism 64 (step S ₁ ). When the charge amount of the battery 68 is in the normal range, the clutch mechanism 64 is in an OFF state. When it is determined that the clutch mechanism 64 is in the OFF state, it is determined whether or not the charge amount of the battery 68 is below a preset threshold value (step S ₂ ). When it is determined that the charge amount of the battery 68 is lower than the threshold value, it is considered that the electric motor 4 may not operate due to insufficient charge of the battery 68, so the battery warning lamp 71 is turned on (step) S ₃ ), stopping the control of the electric brake (that is, the control for operating the electric motor 4 so as to generate a pressing force corresponding to the amount of operation of the brake pedal 62 by the driver) (step S ₄ ), and further the clutch mechanism 64 from the disconnected state switched to the connected state (step _S 5).

  In this state, when the driver depresses the brake pedal 62 shown in FIG. 1, the brake pedal 62 and the wire connector portion 63 swing together, so that the end of the wire cable 5 on the wire connector portion 63 side is pulled. The wire lever 57 of the pressing mechanism 6 is swung by the tensile force acting on the wire cable 5. At this time, the cam member 55 shown in FIG. 8 rotates integrally with the wire lever 57, and the cam surface 60 of the cam member 55 is slid through the link member 56 according to the rotation angle of the cam member 55. Is pushed forward in the axial direction, and the slide member 54 pushes and moves the rotary shaft 14 forward in the axial direction. When the rotary shaft 14 shown in FIG. 6 moves while being pressed forward in the axial direction, the collar portion 51 provided on the outer periphery of the rotary shaft 14 moves the carrier 32 forward in the axial direction. The planetary roller 31 thus moved also moves forward in the axial direction, the outer ring member 15 engaged with the planetary roller 31 also moves forward in the axial direction, and the outer ring member 15 pushes the friction pad 3 forward in the axial direction. As a result, the friction pad 3 is pressed against the brake disc 1.

Thereafter, as shown in FIG. 10, the ON / OFF state of the clutch mechanism 64 is confirmed (step S ₁ ). The clutch mechanism 64 in this state is determined to be ON state, the brake control unit 70, whether the battery charge 68 is above the predetermined threshold (a value larger than the threshold in step S ₂₎ Determination is made (step S ₆ ). When it is determined that the charge amount of the battery 68 exceeds the threshold value, it is considered that the shortage of charge of the battery 68 has been resolved, so the battery warning lamp 71 is turned off (step S ₇ ) and the electric brake Control is started again (step S ₈ ), and the clutch mechanism 64 is switched from the connected state to the disconnected state (step S ₉ ).

  Next, another example of control of the electric motor 4 and the clutch mechanism 64 by the brake control unit 70 will be described with reference to FIG. This control is a control that enables generation of a braking force when the electric motor 4 stops operating due to an electrical failure such as a failure of the pressing force sensor 67 or disconnection of the electrical wiring.

The brake control unit 70 first confirms the ON / OFF state of the clutch mechanism 64 (step S ₁₁ ). When the electric brake is normal, the clutch mechanism 64 is in an OFF state. When it is determined that the clutch mechanism 64 is in the OFF state, it is determined whether or not there is an abnormality in the electric brake (step S ₁₂ ). The determination as to whether or not there is an abnormality in the electric brake is performed, for example, when the pressing force detected by the pressing force sensor 67 is performed when the electric motor 4 is controlled according to the operation of the brake pedal 62 by the driver. It can be performed by a method of detecting whether or not the target value corresponding to the operation amount of the brake pedal 62 is reached and determining that the electric brake is abnormal when the target value is not reached. When it is determined that there is an abnormality in the electric brake, the brake warning light 72 is turned on (step S ₁₃ ), and the electric brake is controlled (ie, the pressing force corresponding to the amount of operation of the brake pedal 62 by the driver). (Control for operating the electric motor 4 so as to occur) is stopped (step S ₁₄ ), and the clutch mechanism 64 is switched from the disconnected state to the connected state (step S ₁₅ ).

  Here, when the electric brake device driven by the electric motor 4 is provided on each of the plurality of wheels, a plurality of wire connector portions 63 and a clutch mechanism 64 are provided on the brake pedal 62 corresponding to each electric brake device, And it can comprise so that only the clutch mechanism 64 corresponding to the electric brake device with abnormality may be made into a connection state.

Thereafter, the brake control unit 70 confirms the ON / OFF state of the clutch mechanism 64 (step S ₁₁ ). In this state, since it is determined that the clutch mechanism 64 is in the ON state, it is determined whether or not the electric brake has returned to normal by self-diagnosis control or the like when the power is turned on (step S ₁₆ ). When it is determined that the electric brake has returned to normal, the brake warning light 72 is turned off (step S ₁₇ ), the electric brake control is started again (step S ₁₈ ), and the clutch mechanism 64 is connected. Is switched to the disconnected state (step S ₁₉ ).

  As described above, even when the electric motor 4 does not operate, the electric brake device pushes the rotating shaft 14 forward in the axial direction by pulling the wire cable 5 by the driver's operation, and the rotating shaft 14 and the outer ring member The friction pad 3 can be pressed against the brake disc 1 by moving 15 in the axial direction forward. Therefore, the braking force can be generated even when an electrical failure occurs. Further, when the rotating shaft 14 is pressed forward in the axial direction, the rotating shaft 14 does not rotate but moves together with the outer ring member 15 in the axial direction forward, so that the rotation of the rotating shaft 14 is hindered for some reason. It is possible to generate a braking force even in the case of

  In addition, this electric brake device can generate a braking force when the driver operates the brake pedal 62 when an electrical failure occurs, as in the case where no electrical failure occurs. is there. Therefore, it is excellent in operability when an electrical failure occurs.

  As the clutch mechanism 64, it is possible to adopt a positive operation type electromagnetic clutch that is connected when energized and disconnected when energization is stopped. It is preferable to employ a reverse operation type electromagnetic clutch that is sometimes configured to be in a connected state. In this way, since the clutch mechanism 64 is in the connected state when the energization to the clutch mechanism 64 is stopped, the braking force can be ensured even when the electric brake device loses power.

  As a motion conversion mechanism that converts the rotation of the rotating shaft 14 to which the rotation of the electric motor 4 is input into the axial movement of the linear motion member that presses the friction pad 3, a mechanism other than the planetary roller mechanism 16 (for example, a feed screw) It is also possible to employ a mechanism or the like. However, when the planetary roller mechanism 16 is employed as in the above embodiment, the planetary roller mechanism 16 has a higher boost ratio (with respect to the rotational torque input to the rotary shaft 14) than other motion conversion mechanisms such as a feed screw mechanism. Therefore, the size of the electric brake device can be reduced. And when this planetary roller mechanism 16 is employ | adopted, the outer ring member 15 which is a linear motion member is united with the rotating shaft 14 in the axial direction front by providing the collar part 51 in the outer periphery of the rotating shaft 14 like the said embodiment. It is possible to move to.

  FIG. 12 shows another example of the pressing mechanism 6. The pressing mechanism 6 includes a linear motion disk 80 disposed on the rear side in the axial direction of the rotary shaft 14, a rotating disk 81 disposed facing the rear side in the axial direction of the linear motion disk 80, and the linear motion disk 80. It has the ball | bowl 82 provided between the moving discs 81, and the wire lever 83 to which the end of the wire cable 5 was connected. The linear motion disk 80 is supported so as to be movable in the axial direction while being prevented from rotating. The rotating disk 81 is supported so as to be rotatable in a state in which the axial rearward movement is restricted by the thrust bearing 84.

  As shown in FIG. 13, a plurality of inclined grooves 86 are formed on the surface of the rotating disk 81 facing the linearly moving disk 80 at intervals in the circumferential direction. Similarly, a plurality of inclined grooves 87 are formed on the surface of the linearly moving disk 80 facing the rotating disk 81 at intervals in the circumferential direction (see FIG. 12).

  As shown in FIGS. 14A and 14B, the inclined groove 86 is formed so as to gradually become shallower from the deepest portion 88 toward one circumferential direction, and the inclined groove 87 is formed from the deepest portion 89 to the other circumference. It is formed to become gradually shallower in the direction. The ball 82 is incorporated between the inclined grooves 86 and 87.

  As shown in FIG. 12, one end of the wire lever 83 is connected to the rotating disk 81, and when the wire cable 5 connected to the other end of the wire lever 83 is pulled, the wire lever 83 and the rotating disk are connected. 81 rotates together. A return spring 89 that urges the wire lever 83 in a direction opposite to the rotating direction of the wire lever 83 due to the pulling operation of the wire cable 5 is attached to the wire lever 83.

  In the pressing mechanism 6, when the wire cable 5 is pulled, as shown in FIG. 14B, the rotating disk 81 is rotated by the tensile force acting on the wire cable 5, and the ball 82 is moved along the inclined groove 86. , 87 rolls in a direction that becomes shallower from the deepest portions 88, 89, the axial distance between the rotating disk 81 and the linearly moving disk 80 increases according to the rotating angle of the rotating disk 81. Here, since the rotation disk 81 is restricted from moving rearward in the axial direction, the linear motion disk 80 moves forward in the axial direction. As a result, the rotary shaft 14 is pushed forward in the axial direction. As a result, the linear motion disk 80 presses the rotary shaft 14 forward in the axial direction, and the rotary shaft 14 is pushed and moved forward in the axial direction.

  In the pressing mechanism 6 shown in FIG. 12, the rotary shaft 14 is directly pressed by the linear motion disk 80, but as shown in FIG. 15, the gear 90 fixed to the outer periphery of the rotary shaft 14 is connected to the linear motion disk 80. And the rotary shaft 14 may be pressed forward in the axial direction via the gear 90.

  FIG. 16 shows another example of the clutch mechanism 64. The brake pedal 62 and the wire connector portion 63 are supported so as to be swingable about a fulcrum shaft 65. Here, the wire connector portion 63 can swing independently of the brake pedal 62 so that the brake pedal 62 can swing away from the wire connector portion 63. A stroke sensor 66 that detects the depression amount of the brake pedal 62 is attached to the brake pedal 62. A wire cable 5 is connected to the end of the wire connector 63 on the swing side.

  The clutch mechanism 64 includes a solenoid mounting member 91 that is swingably supported around a fulcrum shaft 65, a solenoid actuator 92 that is mounted on the solenoid mounting member 91, and a first plunger engagement formed on the brake pedal 62. It has a hole 93 and a second plunger engaging hole 94 formed in the wire connector portion 63. The solenoid actuator 92 has a plunger 95 that advances and retreats in parallel with the fulcrum shaft 65, and is configured such that the plunger 95 advances when energization stops and the plunger 95 retreats when energization. The first plunger engagement hole 93 and the second plunger engagement hole 94 are located on the same line as the plunger 95 of the solenoid actuator 92 in the initial position where the brake pedal 62 is not depressed. Is arranged.

  As shown in FIG. 17, the clutch mechanism 64 advances the plunger 95 of the solenoid actuator 92 so that the brake pedal 62 and the wire connector portion 63 swing together when the driver steps on the brake pedal 62. In this way, the brake pedal 62 and the wire connector 63 can be connected to each other. Further, as shown in FIG. 16, by retracting the plunger 95 of the solenoid actuator 92, the brake pedal 62 and the brake pedal 62 are blocked so that the operating force of the driver acting on the brake pedal 62 is not transmitted to the wire connector portion 63. It can be set as the isolation | separation state which isolate | separates between the wire connector parts 63. FIG. Here, since the plunger 95 of the solenoid actuator 92 moves forward when energization stops and moves backward when energization, the clutch mechanism 64 is in a disconnected state when energized and is connected when energization is stopped. It functions as an electromagnetic clutch.

  FIG. 18 shows an electric brake device according to a second embodiment of the present invention. This electric brake device differs from the first embodiment only in that the end of the wire cable 5 is connected to the parking brake lever 96, and the other points are the same as in the first embodiment. Therefore, the parts corresponding to the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  The wire cable 5 is connected to a parking brake lever 96 that is operated by a driver's hand. The parking brake lever 96 is supported so as to be swingable about the fulcrum shaft 97, and the parking brake lever 96 pulls the wire cable 5 by an operation of manually pulling up the grip 98 provided at the end of the swinging side. It swings. Further, the parking brake lever 96 allows the parking brake lever 96 to swing in the direction in which the grip 98 rises, and prevents the parking brake lever 96 from swinging in the direction in which the grip 98 descends. (Not shown) is built-in. A button 99 for temporarily releasing the ratchet mechanism that prevents the parking brake lever 96 from swinging in the direction in which the grip 98 descends is provided at the tip of the grip 98.

  The electric brake device according to this embodiment performs parking brake that continuously applies a braking force to parked wheels by the driver's operating force, and therefore, the charging amount of the battery 68 that supplies electric power to the electric motor 4 is abnormal. Even when an electrical failure such as a drop, a failure of the pressing force sensor 67, or disconnection of the electrical wiring occurs, the parking brake can be reliably performed and safety is high.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. 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.

DESCRIPTION OF SYMBOLS 1 Brake disc 3 Friction pad 4 Electric motor 5 Wire cable 6 Pressing mechanism 14 Rotating shaft 15 Outer ring member 16 Planetary roller mechanism 31 Planetary roller 32 Carrier 33 Spiral ridge 34 Circumferential groove 51 Gutter 55 Cam member 57 Wire lever 62 Brake pedal 63 Wire connector portion 64 Clutch mechanism 68 Battery 69 Battery sensor 70 Brake control device 80 Direct acting disc 81 Rotating disc 82 Ball 83 Wire lever 86 Inclined groove 87 Inclined groove

Claims (8)

An electric motor (4);
A rotating shaft (14) to which rotation of the electric motor (4) is input;
A linear motion member (15) supported so as to be movable in the axial direction;
A motion conversion mechanism (16) for converting the rotation of the rotation shaft (14) into the axial movement of the linear motion member (15);
A friction pad (3) disposed in front of the linear motion member (15) in the axial direction;
In the electric brake device that presses the friction pad (3) against a brake disk (1) that rotates integrally with a wheel by the linear motion member (15) pressing the friction pad (3),
A pressing mechanism (6) for pressing the rotating shaft (14) forward in the axial direction by a driver's operating force is provided, and when the rotating shaft (14) is pressed by the pressing mechanism (6), the rotating shaft (14 ) And the linear motion member (15) integrally move forward in the axial direction to press the friction pad (3). The linear motion member (15) is an outer ring member (15) arranged so as to surround the rotating shaft (14),
The motion converting mechanism (16) is capable of rotating and revolving a plurality of planetary rollers (31) circumscribing the rotating shaft (14) and simultaneously inscribed in the outer ring member (15), and the planetary rollers (31). Of the planetary roller (31) so as to be engaged with the carrier (32) supported on the inner ring, the spiral ridge (33) provided on the inner periphery of the outer ring member (15), and the spiral ridge (33). A planetary roller mechanism having a circumferential groove (34) or a spiral groove provided on the outer periphery;
2. The electric brake device according to claim 1, wherein a flange portion (51) that supports the carrier (32) from the rear side in the axial direction is provided on an outer periphery of the rotating shaft (14). A brake pedal (62) supported in a swingable manner and operated by a driver's foot;
A wire connector portion (63) that is supported so as to be able to swing independently of the brake pedal (62) and to which the other end of the wire cable (5) connected to the pressing mechanism (6) is connected;
A connection state in which the brake pedal (62) and the wire connector part (63) are connected so that the brake pedal (62) and the wire connector part (63) swing together, and the brake pedal ( 62) is switched to a disconnected state in which the brake pedal (62) and the wire connector portion (63) are disconnected so as to cut off transmission of the driver's operating force acting on the wire connector portion (63) to the wire connector portion (63). The electric brake device according to claim 1 or 2, further comprising a clutch mechanism (64).   The electric brake device according to claim 3, wherein the clutch mechanism (64) is a reverse operation type electromagnetic clutch configured to be in the disconnected state when energized and to be in the connected state when energization is stopped. A battery sensor (69) for detecting a filling amount of a battery (68) for supplying electric power to the electric motor (4);
A control unit (70) for controlling the clutch mechanism (64) based on a detection signal of the battery sensor (69),
The controller (70) disconnects the clutch mechanism (64) when the battery sensor (69) detects that the charge amount of the battery (68) is below a preset threshold. The electric brake device according to claim 3 or 4, wherein control is performed so as to switch from a state to the connected state.   The electric brake device according to claim 1 or 2, wherein the other end of a wire cable (5) having one end connected to the pressing mechanism (6) is connected to a parking brake lever (96) operated by a driver's hand. The pressing mechanism (6)
A cam member (55) which is supported so as to be rotatable about an axis perpendicular to the axial direction of the rotary shaft (14) and has a shape for pressing the rotary shaft (14) forward in the axial direction according to the rotation angle. When,
The electric brake device according to any one of claims 3 to 6, further comprising a wire lever (57) that rotates integrally with the cam member (55) and to which one end of the wire cable (5) is connected. The pressing mechanism (6)
A linear motion disk (80) disposed behind the rotating shaft (14) in the axial direction and supported so as to be movable in the axial direction while being prevented from rotating;
A rotating disk (81) disposed opposite to the axially rearward side of the linearly moving disk (80) and supported so as to be rotatable in a state where movement in the axially rearward direction is restricted;
An inclined groove (87) formed on the surface of the linear disk (80) facing the rotating disk (81) and an inclination formed on the surface of the rotating disk (81) facing the linear disk (80). A ball (82) incorporated between the groove (86);
The electric brake device according to any one of claims 3 to 6, further comprising a wire lever (83) that rotates integrally with the rotating disk (81) and to which one end of the wire cable (5) is connected.

Images