JP2020133866A - Brake device - Google Patents

Abstract

To obtain a novel brake device which is further suppressed in a malfunction while having a constitution capable of suppressing, for example, the exertion of an influence to an electric actuator caused by deposits adhering to a wheel when the wheel rotates.SOLUTION: The brake device comprises, for example: a brake member for switching a brake state for braking a wheel and a release state for releasing a brake of the wheel; a packing plate for supporting the brake member; an electric actuator having a base end connected to the packing plate and a tip extending from the base end, and operating the brake member; and a protector having only a protection part located at a position near the tip rather than the base end as a protection part of a wall-shaped tip which is displaced to the tip in a peripheral direction of the wheel, and stationed with respect to the packing plate.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to a braking device.

Conventionally, a braking device including a braking member that brakes a drum rotor that rotates integrally with a wheel, a backing plate that supports the braking member, and an electric actuator that is provided on the backing plate and operates the braking member is known. (See, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2015-187436

In the braking device of Patent Document 1, for example, when the vehicle moves forward or backward with deposits such as snow and ice adhering to the inner peripheral surface of the wheel when the vehicle is parked, the deposits rotated together with the wheel come into contact with the electric actuator. There was a risk of doing it.

Therefore, one of the problems of the present disclosure is, for example, a novel brake with less inconvenience, which can suppress the influence of the deposits adhering to the wheel on the electric actuator when the wheel rotates. To get the device.

The braking device of the present disclosure is, for example, a braking member that switches between a braking state for braking a wheel and a releasing state for releasing the braking of the wheel, a backing plate for supporting the braking member, and a group coupled to the backing plate. An electric actuator having an end and a tip extending from the base end to operate the braking member, and a wall-shaped tip protection portion displaced in the circumferential direction of the wheel with respect to the tip, which is more than the base end. It has only a protector located near the tip and includes a protector stationary against the backing plate.

According to such a configuration, for example, when the wheel rotates, the protector can prevent the deposits adhering to the wheel from affecting the electric actuator. Further, since the protector has only a protective portion closer to the tip than the base end of the actuator as a wall-shaped protective portion provided at a position shifted in the circumferential direction of the wheel with respect to the tip of the electric actuator. The protector can be configured to be smaller or lighter than a configuration having a protective portion closer to the proximal end than the distal end of the actuator.

FIG. 1 is an exemplary and schematic rear view of the brake device of the embodiment as viewed from the rear of the vehicle. FIG. 2 is an exemplary and schematic side view of the brake device of the embodiment as viewed from the inside in the vehicle width direction. FIG. 3 is an exemplary and schematic rear view of the brake device of the modified example of the embodiment as viewed from the rear of the vehicle. FIG. 4 is an exemplary and schematic side view of the brake device of the modified example of the embodiment as viewed from the inside in the vehicle width direction.

Hereinafter, exemplary embodiments and modifications of the present invention will be disclosed. The configurations of the embodiments and modifications shown below, and the actions and results (effects) brought about by the configurations, are examples. The present invention can also be realized by configurations other than those disclosed in the following embodiments and modifications. Further, according to the present invention, it is possible to obtain at least one of various effects (including derivative effects) obtained by the configuration.

Similar components are included in the following embodiments and variations. Therefore, in the following, a common reference numeral may be given to similar components, and duplicate explanations may be omitted. Further, in the present specification, ordinal numbers are given for convenience in order to distinguish parts, parts, etc., and do not indicate priorities or orders.

Further, in each figure, the arrow X indicates the front of the vehicle, the arrow Y indicates the outside in the vehicle width direction, and the arrow Z indicates the upper side of the vehicle. Further, in the following, unless otherwise specified, the axial direction of the rotation center Ax is simply referred to as the axial direction, the radial direction of the rotation center Ax is simply referred to as the radial direction, and the circumferential direction of the rotation center Ax is simply referred to as the circumferential direction. Will be done.

[Embodiment]
FIG. 1 is a rear view of the brake device 2 for a vehicle of the embodiment from the rear of the vehicle, and FIG. 2 is a side view of the brake device 2 from the inside in the vehicle width direction. As shown in FIG. 1, the brake device 2 is housed inside the peripheral wall 1a of the cylindrical wheel 1. The brake device 2 is a so-called drum brake. The brake device 2 includes two brake shoes 3 which are separated from each other in the front-rear direction. The two brake shoes 3 extend in an arc shape along the inner peripheral surface of a cylindrical drum rotor (not shown). The drum rotor rotates integrally with the wheel 1 around the rotation center Ax along the vehicle width direction (direction Y). The brake device 2 moves the two brake shoes 3 so as to come into contact with the inner peripheral surface of the cylindrical drum rotor. As a result, the friction between the brake shoe 3 and the drum rotor brakes the drum rotor and thus the wheel 1. The brake shoe 3 is an example of a braking member.

The brake device 2 includes a wheel cylinder (not shown) operated by hydraulic pressure and a motor 120 operated by energization as an actuator for moving the brake shoe 3. The wheel cylinder and the motor 120 can each move two brake shoes 3. The wheel cylinder is used, for example, for braking during traveling, and the motor 120 is used, for example, for braking during parking. That is, the brake device 2 is an example of an electric parking brake. The motor 120 may be used for braking during traveling.

The brake device 2 includes a disk-shaped backing plate 4. The backing plate 4 is provided in a posture intersecting the rotation center Ax of the wheel 1. That is, the backing plate 4 spreads substantially along the direction intersecting the rotation center Ax, specifically, substantially along the direction orthogonal to the rotation center Ax. The components of the brake device 2 are provided on both the outside and the inside of the backing plate 4 in the vehicle width direction. The backing plate 4 directly or indirectly supports each component of the braking device 2. Further, the backing plate 4 is connected to a connecting member (not shown) with the vehicle body. The connecting member is, for example, a part of the suspension (for example, an arm, a link, a mounting member, etc.). The brake device 2 can be used for both driving wheels and non-driving wheels.

As shown in FIG. 1, the electric actuator 100 is fixed to the backing plate 4 in a state of protruding from the inner surface 4a of the backing plate 4 in the vehicle width direction to the side opposite to the brake shoe 3. The electric actuator 100 includes a housing 110, a motor 120, a speed reduction mechanism 130, a motion conversion mechanism 140, a cable (not shown), and a control device (not shown).

As shown in FIG. 2, the housing 110 extends in a direction intersecting the radial direction when viewed in the axial direction.

As shown in FIGS. 1 and 2, the housing 110 supports the motor 120, the speed reduction mechanism 130, and the motion conversion mechanism 140. The housing 110 has a lower case 112, a middle case 113, a first upper case 114, and a second upper case 115. These parts are integrated by fittings such as screws and bolts, insert molding, and the like.

The lower case 112 is made of a metal material such as an aluminum alloy. In this case, the lower case 112 can be manufactured, for example, by die casting. The base end 112a of the lower case 112 is fixed to the inner surface 4a of the backing plate 4 in the vehicle width direction by a connector such as a weld or a screw or a bolt. The base end 112a is the base end of the electric actuator 100. The lower case 112 is also referred to as a base, a body, or the like.

Further, the middle case 113, the first upper case 114, and the second upper case 115 are made of, for example, a synthetic resin material. The motor 120 is housed in the first upper case 114 and is covered by the wall portion of the first upper case 114. Further, the motion conversion mechanism 140 and the deceleration mechanism 130 are housed in the second upper case 115 and are covered by the wall portion of the second upper case 115. The central axis of the motor 120 (not shown) and the central axis of the rotating member of the motion conversion mechanism 140 (not shown) are parallel to each other. The configuration of the housing 110 is not limited to this example.

As shown in FIGS. 1 and 2, the first upper case 114 is separated from the second upper case 115 in one of the circumferential directions. The first upper case 114 and the second upper case 115 are at least partially aligned in the circumferential direction. Further, the second upper case 115 projects radially outward from the backing plate 4 with respect to the first upper case 114. That is, in the present embodiment, as an example, the radial outer end 115a of the second upper case 115 is the position closest to the inner peripheral surface 1b of the wheel 1 in the electric actuator 100. The end 114a and the end 115a may also be referred to as a tip. The ends 114a and 115a are examples of the tips of the electric actuator 100.

The motor 120 has, for example, a stator, a rotor, a coil, a magnet, an output shaft, and the like (all not shown). The output shaft is part of the rotor. The motor 120 is controlled by a control device to rotate the rotor and output shaft. The motor 120 may also be referred to as an actuator or a rotation source.

The speed reduction mechanism 130 includes a plurality of gears rotatably supported by the housing 110, rotates in conjunction with the output shaft of the motor 120, and decelerates.

The motion conversion mechanism 140 has a rotating member, a linear motion member, and a detent guide (all not shown). The motion conversion mechanism 140 is an example of a rotary linear motion conversion mechanism.

The control device that controls the motor 120 is, for example, an ECU (electronic control unit). A part of the control device may be composed of hardware such as a central processing unit (CPU) or a controller that executes software, or the control device may be composed entirely of hardware. The control device may also be referred to as a control unit.

In the above configuration, the rotation of the output shaft of the motor 120 is transmitted to the rotating member of the motion conversion mechanism 140 via the reduction mechanism 130. The motion conversion mechanism 140 has, for example, a screw mechanism. In this case, the rotating member is provided with one of the male and female threads that mesh with each other, and the linear motion member is provided with the other of the male and female threads. The housing 110 is provided with a detent guide that limits the rotation of the linear motion member and guides the linear motion member in the linear motion direction. In such a configuration, since the detent guide limits the rotation of the linear motion member and guides the linear motion member in the linear motion direction, the linear motion member moves linearly in accordance with the rotation of the rotary member. Along with the linear motion of the linear motion member, an operating member such as a cable or a rod that interlocks with the linear motion member moves linearly, and in conjunction with the actuating member, the brake shoe 3 is not in the braking position (not shown). Move to and from the braking position (not shown). The state in which the brake shoe 3 is located in the braking position is the braking state, and the state in which the brake shoe 3 is located in the non-braking position is the non-braking state.

Further, in the present embodiment, the brake device 2 is provided with the barrier 7. The barrier 7 is coupled to the backing plate 4 and is stationary with respect to the backing plate 4. The barrier 7 is made of a metallic material such as an iron-based material. The barrier 7 is made by, for example, pressing or bending a plate material. Further, the barrier 7 is fixed to the inner surface 4a of the backing plate 4 in the vehicle width direction by welding or a binder such as a screw or a bolt. The barrier 7 prevents an deposit (not shown) that adheres to the wheel 1 such as snow or ice and rotates with the wheel 1 from hitting the electric actuator 100. Barrier 7 is an example of a protector.

As shown in FIG. 2, the barrier 7 is arranged so as to be generally separated from the electric actuator 100 in the circumferential direction when viewed from the inside (axial direction) in the vehicle width direction. In the present embodiment, as an example, the barrier 7 is separated from the electric actuator 100 in the counterclockwise direction around the center of rotation Ax.

As shown in FIG. 1, the barrier 7 extends from the backing plate 4 in the axial direction (inward in the vehicle width direction). The end portion 7c of the barrier 7 inward in the vehicle width direction is located inward in the vehicle width direction with respect to the ends 114a and 115a.

Further, the barrier 7 has a convex portion 7a protruding in a direction intersecting the axial direction (vehicle width direction). The convex portion 7a constitutes a ridge line 7a1 that extends in the axial direction and is sharp in the direction intersecting the axial direction. The convex portion 7a and the ridge line 7a1 project in the circumferential direction. The ridge line 7a1 does not have to be completely along the axial direction, and may be inclined with respect to the axial direction. Further, the ridge line 7a1 extends in a direction intersecting the surface 4a of the backing plate 4. The ridge line 7a1 may also be referred to as an edge. The convex portion 7a may also be referred to as a bent portion. The convex portion 7a is an example of a protruding portion.

Of the barrier 7, the wall-shaped portion that is displaced in the circumferential direction with respect to the ends 114a and 115a and intersects the circumferential direction is the protective portion 7b. In the present embodiment, the protection portion 7b is provided only at a portion closer to the ends 114a, 115a (tip) than the base end 112a of the electric actuator 100, and is provided from the ends 114a, 115a (tip) of the electric actuator 100. Is not provided at a portion near the base end 112a. Further, as an example, the protective portion 7b is adjacent to or close to the end portions 114a and 115a with a gap.

As described above, the brake device 2 has a barrier 7 (protector), and the barrier 7 suppresses deposits (not shown) rotating together with the wheel 1 from hitting the electric actuator 100. Therefore, according to such a configuration, it is possible to suppress the influence of the deposits adhering to the wheel 1 on the electric actuator 100.

Further, the protective portion 7b located on the barrier 7 so as to be displaced in the circumferential direction with respect to the end portions 114a and 115a is provided only on the side closer to the end portions 114a and 115a (tip) than the base end 112a of the electric actuator 100. , The electric actuator 100 is not provided on the side closer to the base end 112a than the ends 114a and 115a. In a so-called cantilever support structure in which the base end 112a of the electric actuator 100 is supported and the ends 114a and 115a of the electric actuator 100 are free ends, the point of action of the external force is the end 114a rather than the base end 112a. , 115a, in other words, the farther away from the base end 112a, the larger the rotational moment acting on the support portion. Therefore, according to such a configuration, for example, the base end 112a of the electric actuator 100 is driven by the external force applied by the barrier 7 having the protective portion 7b provided on the side closer to the ends 114a and 115a than the base end 112a. Therefore, it is possible to suppress the generation of a large rotational moment, and by extension, the deformation or breakage of the portion of the backing plate 4 to which the base end 112a is attached is likely to be suppressed. It should be noted that such an effect by the protection unit 7b can be obtained not only for the electric actuator 100 extending in the circumferential direction and the tangential direction, but also for the electric actuator 100 extending in various directions such as the axial direction and the radial direction. Is. The "coupling of the electric actuator 100 and the barrier 7 to the backing plate 4" is not limited to direct coupling, but is indirect such that an intermediate member and other members such as brackets and washers intervene. Also includes binding.

Further, according to the configuration in which the protective portion 7b is provided only on the side closer to the ends 114a and 115a than the base end 112a, the protective portion 7b is not provided on the side closer to the end portions 114a and 115a than the base end 112a. Compared with the configuration provided only on the side closer to the base end 112a than the end portions 114a and 115a, the distance between the protective portion 7b and the end portions 114a and 115a is smaller, and deposits are less likely to be present at the distance. Therefore, the ends 114a and 115a can be protected more reliably. Further, according to the configuration, as compared with the configuration in which the protective portion 7b is provided on both the side closer to the end ends 114a and 115a than the base end 112a and the side closer to the base end 112a than the end portions 114a and 115a. , The barrier 7 can be realized as a smaller or lighter configuration.

Further, in the present embodiment, the electric actuator 100 extends so as to intersect the radial direction when viewed from the axial direction, and the protective portion 7b is provided adjacent to the end portions 114a and 115a in the circumferential direction. ing. According to such a configuration, for example, in the electric actuator 100 in which the protection portion 7b extends so as to intersect the radial direction when viewed from the axial direction, the end portions 114a and 115a can be more reliably protected.

Further, in the present embodiment, the entire barrier 7 (protector) is displaced in the circumferential direction with respect to the electric actuator 100. According to such a configuration, for example, a worker such as a human or a robot, with one of the barrier 7 and the electric actuator 100 attached, directs the other toward or from the other attachment position. Since it can be moved in the axial direction, the barrier 7 and the electric actuator 100 can be attached and detached more easily, and the degree of freedom in the assembly process of the brake device 2 including the barrier 7 and the electric actuator 100 is increased, and the brake is applied. Advantages such as reduction of labor and cost required for manufacturing and maintenance of the device 2 can be obtained.

Further, in the present embodiment, the barrier 7 has a convex portion 7a (protruding portion) protruding in a direction intersecting the axial direction (here, a circumferential direction). According to such a configuration, for example, the cross-sectional coefficient of the barrier 7 is higher than that of a flat barrier without the convex portion 7a, and thus the rigidity and strength are higher. Therefore, the barrier 7 is a deposit that rotates together with the wheel 1. It is less likely to be deformed or damaged even when pressed by.

Further, in the present embodiment, the convex portion 7a protrudes in a direction away from the end portions 114a and 115a (here, in the circumferential direction, the side opposite to the side where the end portions 114a and 115a are located). If the barrier 7 has a recess that is recessed in the direction of approaching the ends 114a and 115a, deposits that rotate with the wheel 1 may accumulate in the recess. In this regard, according to the convex portion 7a protruding in the direction away from the end portions 114a and 115a, for example, it is possible to prevent the barrier 7 from accumulating deposits rotating together with the wheel 1.

Further, the barrier 7 has a ridge line 7a1 that protrudes in a direction away from the ends 114a and 115a and extends so as to intersect the surface 4a of the backing plate 4. The ridge line 7a1 can break the deposits that rotate with the wheel 1. Therefore, according to such a configuration, for example, the barrier 7 can also function as a scraper having the ridge line 7a1 as an edge, so that the deposits adhering to the wheel 1 further suppress the influence on the electric actuator 100. can do. The outer surface (end surface) of the ridge line 7a1 may be sharply pointed or may be a curved surface having a relatively small radius of curvature.

[Modification example]
FIG. 3 is a rear view of the brake device 2A for a vehicle of a modified example of the embodiment from the rear of the vehicle, and FIG. 4 is a side view of the brake device 2A from the inside in the vehicle width direction. The brake device 2A of this modification has the same components as the brake device 2 of the above embodiment. Therefore, according to the brake device 2A, the same action and effect based on the same component can be obtained. However, in this modification, the configuration of the electric actuator 100A is different from that of the above embodiment.

Specifically, as shown in FIGS. 3 and 4, the housing 110A has a cylindrical shape, and the cylindrical lower case 112 and the cylindrical upper case 116 are connected in series.

The motor 120 is housed in the upper case 116, and the motion conversion mechanism 140 is housed in the lower case 112. Further, the speed reduction mechanism 130 is housed inside at least one of the lower case 112 and the upper case 116. In the housing 110A, the motor 120, the speed reduction mechanism 130, and the motion conversion mechanism 140 are arranged in series. Of the motor 120, the reduction mechanism 130, and the motion conversion mechanism 140, the motion conversion mechanism 140 is located closest to the base end 112a of the lower case 112.

As shown in FIG. 3, the base end 112a is joined to the inner surface 4a of the backing plate 4 in the vehicle width direction by a connector such as a weld or a screw or a bolt, and is joined to the base end 112a of the upper case 116. The opposite end 116a is separated from the surface 4a. The housing 110A extends along a virtual plane approximately orthogonal to the center of rotation Ax.

Further, as shown in FIG. 4, the housing 110A has a direction intersecting the radial direction, a circumferential direction of the rotation center Ax, or a tangential direction of a virtual circle centered on the rotation center Ax when viewed in the axial direction. Extends to.

The barrier 7A is fixed to the backing plate 4 and is stationary with respect to the backing plate 4. The barrier 7A is positioned so as to be displaced in the circumferential direction with respect to the end portion 116a as a whole, and functions as a protective portion 7b. That is, also in this modification, the protective portion 7b is located only on the side closer to the end portion 116a (tip) than the base end 112a, and the same effect as that of the above-described embodiment can be obtained.

Although the embodiments and modifications of the present invention have been illustrated above, the above-described embodiments and modifications are examples, and the scope of the invention is not intended to be limited. The above-described embodiment and modification can be implemented in various other forms, and various omissions, replacements, combinations, and changes can be made without departing from the gist of the invention. In addition, specifications such as each configuration and shape (structure, type, direction, type, size, length, width, thickness, height, number, arrangement, position, material, etc.) are changed as appropriate. Can be carried out. For example, the protruding portion of the protector may be a protruding fin or a wall.

For example, in the above-described embodiment and modification, the protection unit and the protector are provided so as to be offset in the counterclockwise direction around the center of rotation with respect to the electric actuator when viewed from the inside in the vehicle width direction. It is not limited, and may be provided so as to be offset in the clockwise direction with respect to the electric actuator.

1 ... Wheel, 2, 2A ... Brake device, 3 ... Brake shoe (braking member), 4 ... Backing plate, 7 ... Barrier (protector), 7a ... Convex part (protruding part), 7b ... Protection part, 100, 100A ... Electric actuator, 112a ... base end, 114a, 115a, 116a ... end (tip).

Claims (5)

A braking member that switches between a braking state that brakes the wheel and a release state that releases the braking of the wheel.
A backing plate that supports the braking member and
An electric actuator having a base end coupled to the backing plate and a tip extending from the base end to operate the braking member, and an electric actuator.
It has only a protective portion located closer to the tip than the base end as a wall-shaped protective portion of the tip that is displaced in the circumferential direction of the wheel with respect to the tip, and is stationary with respect to the backing plate. With the protector
With a braking device. The electric actuator extends so as to intersect the radial direction of the wheel when viewed from the axial direction of the wheel.
The brake device according to claim 1, wherein the protective portion is provided with a gap from the tip. The brake device according to claim 1 or 2, wherein the entire protector is provided so as to be offset from the electric actuator in the circumferential direction. The brake device according to any one of claims 1 to 3, wherein the protector has a protruding portion protruding in a direction intersecting the axial direction of the wheel. The brake device according to claim 4, wherein the protruding portion protrudes away from the tip.

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