JP5488234B2 - Brake device, friction pair for brake device and brake pad - Google Patents

Description

  The present invention relates to a brake device, a friction pair for a brake device, and a brake pad.

  As a conventional brake device such as a disc brake, Patent Document 1 discloses, for example, that a pad friction plane of a brake pad is pressed against a disc friction plane of a disc rotor that rotates together with a wheel to slide between the disc friction plane and the pad friction plane. Accordingly, there has been disclosed a friction surface coating for a friction material of a brake device that applies a braking force to a wheel by a friction force generated between the two.

JP 2000-226552 A

  By the way, the friction surface coating for a friction material of a brake device described in Patent Document 1 as described above has room for further improvement in terms of friction performance, for example.

  This invention is made | formed in view of said situation, Comprising: It aims at providing the brake device which can optimize friction performance, the friction pair for brake devices, and a brake pad.

In order to achieve the above object, the brake device according to the present invention is provided in contact with the rolling member, a first member having a rolling member and a cage that rotatably holds the rolling member, and the first member. A second member that rotates the rolling element with the cage in accordance with relative displacement with the member; and a pressing mechanism that presses the first member and the second member; the first member and the second member The friction generated between the rolling element and the cage when the second member rotates the rolling element in association with the relative displacement between the first member and the second member. The relative displacement is braked by a force, and a film is provided on at least one of the contact surfaces of the rolling element and the second member.

  In the brake device, the film may be formed of a thermoplastic resin.

  In the brake device, the film may be provided in a thickness range of 0.1 [mm] or more.

  Moreover, in the said brake device, the said film | membrane shall be provided in the contact surface with the said 2nd member of the said rolling element.

  Moreover, in the said brake device, the said rolling element shall be comprised with a hard material.

  Further, in the brake device, the cage and the second member have a configuration in which a force for rotating the rolling element by the second member is larger than a force for holding the rolling element by the cage. can do.

  Moreover, in the said brake device, the said 1st member cannot be rotated with a wheel, and the said 2nd member shall be rotatable with the said wheel.

In order to achieve the above object, a friction pair for a brake device according to the present invention is provided in contact with a first member having a rolling element and a cage that rotatably holds the rolling element, and the rolling element. A second member that rotates the rolling element with the cage in accordance with relative displacement with the first member, and the first member and the second member are pressed against each other. When the second member rotates the rolling element in association with the relative displacement with the second member, the relative displacement is braked by a frictional force generated between the rolling element and the cage, and the rolling element A film is provided on at least one of the contact surfaces with the second member.

To achieve the above object, a brake pad according to the present invention, the surface of the side pressed against by a disc rotor rotating with a wheel, and a cage for rotatably holding the rolling elements and the rolling elements, wherein When the disk rotor is rotated against the disk rotor in a state of being pressed against the disk rotor, the relative displacement is caused by a frictional force generated between the rolling element and the cage. Brake is applied, and a film is provided on the contact surface of the rolling element with the disk rotor.

  The brake device, the brake pair for brake device, and the brake pad according to the present invention have an effect that the friction coefficient can be stabilized and the friction performance can be optimized.

Drawing 1 is a fragmentary sectional view showing a schematic structure of a friction pair for brake devices concerning an embodiment. FIG. 2 is a schematic partial cross-sectional view of the rolling element according to the embodiment. FIG. 3 is a schematic diagram illustrating a schematic configuration of the brake device according to the embodiment. FIG. 4 is a schematic exploded perspective view showing a layer structure of a friction pair for a brake device according to the embodiment. FIG. 5 is a perspective view schematically showing the surface shape of the contact wall surface with the rolling element of the cage according to the embodiment.

  Hereinafter, embodiments of a brake device, a friction pair for a brake device, and a brake pad according to the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by this embodiment. In addition, constituent elements in the following embodiments include those that can be easily replaced by those skilled in the art or those that are substantially the same.

[Embodiment]
1 is a partial cross-sectional view showing a schematic configuration of a friction pair for a brake device according to an embodiment, FIG. 2 is a schematic partial cross-sectional view of a rolling element according to the embodiment, and FIG. 3 is a brake device according to the embodiment. FIG. 4 is a schematic exploded perspective view showing a layer structure of a friction pair for a brake device according to the embodiment, and FIG. 5 is a contact wall surface with the rolling element of the cage according to the embodiment. It is a perspective view which shows typically the surface shape of this.

  As shown in FIGS. 1 and 3, the brake device 1 according to the present embodiment is typically mounted on a vehicle and applies braking force to wheels that are rotatably supported on the vehicle body of the vehicle. A brake device friction pair 2 and an actuator 3 as a pressing mechanism are provided.

  The brake device friction pair 2 is for generating a predetermined friction force (friction resistance force) between the friction elements when a braking force is applied to the wheel. The brake device friction pair 2 includes a brake pad 4 as a first member and a disk rotor 5 as a second member. A pair of brake pads 4 are provided on the vehicle body side so as not to rotate together with the wheels. The disk rotor 5 is provided on the wheel side so as to be integrally rotatable with the wheel. As a result, the brake pad 4 and the disk rotor 5 are configured to be relatively displaceable, that is, have a relationship capable of relative rotation in the rotational direction of the disk rotor 5. The pair of brake pads 4 are disposed on both sides of the disk rotor 5 and face the contact surfaces 5 a on both sides of the disk rotor 5. The pair of brake pads 4 sandwich both sides of the disk rotor 5 according to the operation of the actuator 3.

  The actuator 3 presses the brake pad 4 and the disc rotor 5 when a braking force is applied to the wheel. As shown in FIG. 3, the actuator 3 has a caliper 6 and a piston 7. The caliper 6 has a U-shape straddling the disc rotor 5 and is supported by a bracket (not shown) fixed to the vehicle body side. The caliper 6 supports the pair of brake pads 4 so as to be able to approach and separate from the contact surface 5 a of the disk rotor 5. The caliper 6 includes a cylinder portion 9 provided with a cylinder mechanism 8 that allows the piston 7 to move back and forth, a reaction portion 10 that is disposed on the opposite side of the cylinder portion 9 with the disc rotor 5 interposed therebetween, and the cylinder portion 9 and the reaction The connecting part 11 that connects the part 10 is included. The pair of brake pads 4 includes an inner pad disposed on the cylinder portion 9 side of the caliper 6 and an outer pad disposed on the reaction portion 10 side. In the cylinder mechanism 8, a piston 7 is movably supported by a cylinder portion 9, and a hydraulic pressure chamber 12 is defined by the cylinder portion 9, the piston 7, a seal, and the like. The tip of the piston 7 faces the brake pad (inner pad) 4.

  Therefore, for example, when the hydraulic fluid is supplied to the hydraulic chamber 12 and pressurized according to the brake pedal depression operation by the driver, the brake device 1 moves the piston 7 in the direction of arrow A (the brake pad (inner pad) 4 The front end of the piston 7 presses one brake pad 4, and the one brake pad 4 can be brought close to one contact surface 5 a of the disk rotor 5. . At this time, the caliper 6 moves forward in the direction opposite to that of the piston 7, that is, in the direction indicated by the arrow B (the direction in which the brake pad (outer pad) 4 approaches the disc rotor 5) due to the moving reaction force of the piston 7 moving forward. The other brake pad 4 can be brought close to the other contact surface 5 a of the disk rotor 5. In the brake device 1, when each brake pad 4 comes into contact with and presses against each contact surface 5 a of the disk rotor 5 to sandwich the disk rotor 5, a predetermined rotational resistance force is applied to the disk rotor 5 that rotates together with the wheels. Acting, a braking force can be applied to the disk rotor 5 and the wheels rotating integrally therewith. In the brake device 1, when the hydraulic chamber 12 is depressurized, the piston 7 and the caliper 6 are returned to predetermined positions, and each brake pad 4 is separated from the disc rotor 5.

  By the way, as shown in FIG. 1, in the brake device 1 of the present embodiment, a rolling element 42 and the rolling element 42 are provided on the surface on the side where the brake pad 4 forming the friction pair 2 for the brake device is pressed against the disc rotor 5. For example, regardless of the projected area of the surface on the side where the brake pad 4 is pressed against the disk rotor 5, the friction performance or Performances such as wear resistance can be suitably set. Here, the surface of the brake pad 4 that is pressed against the disk rotor 5 is the surface of the brake pad 4 that faces the contact surface 5 a of the disk rotor 5.

  In FIG. 1, the depth direction in the figure is the direction of relative displacement between the brake pad 4 and the disk rotor 5, that is, the rotational direction of the disk rotor 5. The brake pad 4 is described as having a common configuration unless the inner pad and the outer pad need to be distinguished from each other because the inner pad and the outer pad have substantially the same configuration.

  When the brake pad 4 is pressed against the rotating disk rotor 5, the brake device 1 rotates while the rolling element 42 is held by the holder 43, so that the rolling element 42 and the rolling element 42 are rotated according to the rotation of the rolling element 42. Relative displacement between the brake pad 4 and the disk rotor 5, that is, a braking force for braking the rotation of the disk rotor 5 is generated by the frictional force (frictional resistance force) generated between the cage 43. The brake device 1 employs a structure in which the rolling elements 42 arranged on the surface of the brake pad 4 that is pressed against the disc rotor 5 can roll (rotate) on the spot. The brake device 1 rotates the rolling element 42 by the disk rotor 5 that rotates together with the wheels, and frictionally brakes the rotating rolling element 42 on the cage 43 side.

  Specifically, as shown in FIGS. 1 and 4, the brake pad 4 includes a contact portion 41, a support member 44, a support member 45, an absorption member 46, and the like. The brake pad 4 has a layer structure in the order of the contact portion 41, the support member 44, the absorbing member 46, and the support member 45 from the surface pressed against the disk rotor 5 (surface facing the contact surface 5 a). In 41, the rolling element 42 is held by the holder 43.

  The contact portion 41 is a portion that comes into contact with the disc rotor 5 at the time of braking in the brake pad 4, and here includes a rolling element 42 and a holder 43.

  The rolling element 42 is rotatable along the direction of relative displacement between the brake pad 4 and the disk rotor 5, that is, the rotation direction of the disk rotor 5. The rolling element 42 is disposed between a contact surface 5a of the disk rotor 5 and a contact wall surface 43a of a retainer 43 described later, and the contact surface 5a and the contact wall surface when the brake pad 4 is pressed against the disk rotor 5. 43a is contacted. The rolling element 42 is a sphere (spherical member). And this rolling element 42 is comprised with what is called a hard material like the disk rotor 5 mentioned later. The rolling element 42 is typically made of a material having a relatively high heat resistance, a predetermined strength or higher, and a relatively high hardness, such as alumina or silicon nitride, as a hard material.

  As described above, the retainer 43 is in contact with the rolling element 42 and holds the rolling element 42 so as to be rotatable on the spot. The holder 43 basically holds the rolling element 42 so as not to be relatively displaceable and capable of rotating (rotating). The cage 43 holds the rolling element 42 such that the rotation axis of the rolling element 42 is substantially orthogonal to the rotation direction of the disk rotor 5 and the pressing direction by the actuator 3. The rolling element 42 is placed on the spot so that the axis of rotation of the rolling element 42 does not move by the cage 43 while contacting the cage 43 and the disc rotor 5 with the relative displacement (relative rotation) between the brake pad 4 and the disc rotor 5. Rotate around the axis of rotation while being held at. The cage 43 is typically made of a material having relatively high heat resistance and a predetermined strength or more, such as tungsten or carbide.

  Here, the cage 43 is formed in a cylindrical shape in accordance with the shape of the rolling element 42, and the rolling element 42 is placed on the surface that is pressed against the disk rotor 5, that is, the surface that contacts the rolling element 42. A holding groove 43b is provided. In this holding groove 43 b, the contact wall surface 43 a with the rolling element 42 is inclined with respect to the rotational axis direction of the rolling element 42 and the pressing direction by the actuator 3.

  As shown in FIG. 5, the holding groove 43b is formed in a shape in which the contact wall surface 43a inclined as described above forms a curved surface. Although the holding groove 43b is described as being formed in a conical shape, it may be formed in a truncated cone shape. The holding groove 43 b is positioned on the side where the conical bottom side is pressed against the disk rotor 5. In the holding groove 43 b, for example, the inner diameter of the conical bottom surface is larger than the outer diameter of the rolling element 42. A part of the rolling element 42 is held in the holding groove 43b. Therefore, the holding groove 43b and the rolling element 42 are in contact with the contact wall surface 43a that is the inner surface of the holding groove 43b and the outer surface of the rolling element 42, and this contact portion forms a circle.

  The support member 44 and the support member 45 are so-called back metal that supports the contact portion 41. The brake pad 4 is assembled so that the support member 44 and the support member 45 overlap with each other, whereby a back metal for supporting the contact portion 41 is configured. The support member 44 and the support member 45 support the retainer 43 of the contact portion 41.

  More specifically, the support member 44 here is for positioning the retainer 43 at a predetermined position. The brake pad 4 has a plurality of sets of contact portions 41 each composed of a combination of a rolling element 42 and a holder 43 that holds the rolling element 42, that is, a plurality of rolling elements 42 and a plurality of holders 43 are provided. The support member 44 positions each of the plurality of cages 43 at predetermined positions.

  The support member 44 is configured by a plate-like member, and is provided with an installation hole 44a as an accommodation-side recess. The installation hole 44 a is a recess that accommodates the rolling elements 42 and the retainer 43, and here penetrates the support member 44 in a cylindrical shape in the pressing direction by the actuator 3. A plurality of installation holes 44 a are provided corresponding to the plurality of cages 43. Each cage 43 is inserted and positioned in each installation hole 44a. Thereby, the support member 44 can restrain the movement of each retainer 43 so that each retainer 43 does not relatively move in a direction other than the pressing direction by the actuator 3 (typically, the pad surface direction).

  The support member 45 is a plate-like support member on which a pressing force from the actuator 3 acts, and forms the base of the brake pad 4. The support member 45 is configured by a plate-like member, and the brake pad 4 is formed on the caliper 6 (see FIG. 3) so that the support member 45 comes into contact with the piston 7 (see FIG. 3) and the reaction unit 10 (see FIG. 3). 3).

  The absorbing member 46 is sandwiched by the support member 44 on the side pressed against the disk rotor 5 and the support member 45 on the opposite side (back side) with respect to the pressing direction by the actuator 3, and the relative positional relationship is fixed. The

  Here, as shown in FIG. 1, the supporting member 44 is provided with a slip-off preventing portion 47 on the surface that is pressed against the disk rotor 5 in the pressing direction by the actuator 3. The drop prevention part 47 is formed as a part of the support member 44 where the diameter of the installation hole 44a is reduced. Each rolling element 42 is held by each retainer 43, so that a part of the outer surface protrudes on the opposite side of each retainer 43 with respect to the pressing direction by the actuator 3 with the drop prevention portion 47 interposed therebetween. To expose. As a result, the slip prevention part 47 can prevent the rolling element 42 from falling off and can make the outer surface of the rolling element 42 exposed from each opening contact the contact surface 5 a of the disk rotor 5.

  The rolling elements 42, the retainers 43, and the support members 44 are pressed by the actuator 3 in a state where the retainers 43 are inserted into the respective installation holes 44a and the respective rolling elements 42 are retained in the respective retaining grooves 43b. The relative positional relationship is fixed by being sandwiched between the removal preventing portion 47 and the absorbing member 46 with respect to the direction. The brake pad 4 is provided with an absorbing member 46 on the back side of the plurality of cages 43, that is, on the side opposite to the side pressed against the disc rotor 5.

  The absorbing member 46 is provided between the support member 45 and the plurality of cages 43 with respect to the pressing direction by the actuator 3. The absorbing member 46 can absorb the displacement of the cage 43 that forms the contact portion 41, and can thereby absorb the displacement of the rolling element 42 that forms the contact portion 41. The absorbing member 46 absorbs the displacement of the plurality of cages 43 with respect to the support members 44 and 45 when a force in the pressing direction by the actuator 3 is applied. The absorbing member 46 is a sheet-like elastic body, and is typically made of a material having relatively high heat resistance and a predetermined strength or more, such as a metal leaf spring, titanium, stainless steel, or the like. The absorbing member 46 is preferably made of a material having a relatively wide elastic range as compared with the supporting members 44 and 45. The absorbing member 46 is elastically deformed when a pressing force by the actuator 3 is applied, thereby permitting and absorbing the displacement along the pressing direction of each contact portion 41 by the actuator 3, and the pressing force according to the displacement. And a pressing force is applied to the plurality of cages 43 almost uniformly.

  Returning to FIG. 1 and FIG. 4, the support member 45 of the present embodiment is provided with an escape portion 45 a as a flexure-side recess. The escape portion 45 a is provided on the opposite side of the retainer 43 with the absorbing member 46 interposed therebetween. The escape portion 45 a penetrates the support member 45 in a columnar shape in the pressing direction by the actuator 3. A plurality of escape portions 45 a are provided corresponding to the plurality of cages 43.

  Here, the escape portion 45a has a diameter larger than the diameter of the installation hole 44a. Further, the absorbing member 46 is provided with a cylindrical through hole 46a at the center of the contact portion with the cage 43. Furthermore, the contact part 41 has a protrusion 43 c that protrudes toward the absorption member 46 at the center part of the contact part with the absorption member 46, here the center part of the contact part with the absorption member 46 of the cage 43. Accordingly, the brake pad 4 is configured such that the amount of deflection at the center of the contact portion with the contact portion 41 of the absorbing member 46 is larger than the amount of deflection at the edge of the contact portion with the contact portion 41 of the absorbing member 46. Can do. As a result, the brake pad 4 can increase the displacement absorption rate of the absorbing member 46 and can improve the dispersion effect of the pressing force by the actuator 3 by the absorbing member 46.

  The brake pad 4 is an actuator in a state where the relative positional relationship of the contact portion 41, the support member 44, the support member 45, and the absorption member 46 including the rolling elements 42 and the retainer 43 configured as described above is fixed. 3, the slip prevention part 47, the rolling element 42, the retainer 43, the installation hole 44 a and the escape part 45 a face each other.

  The disk rotor 5 is provided in contact with the rolling element 42 and rotates the rolling element 42 with the holder 43 in accordance with the relative displacement with the brake pad 4. The disk rotor 5 is formed in a disk shape that can rotate around the rotation axis. The disk rotor 5 is made of a hard material similar to the rolling element 42.

  The brake device 1 is configured so that the disc rotor 5 rotates the rolling element 42 by the retainer 43 in accordance with the relative displacement between the brake pad 4 and the disc rotor 5, in other words, a disc that rotates with the wheels. The configuration for rotating the rolling element 42 by the rotor 5 and causing the rolling element 42 to rub on the cage 43 side has the following configuration. That is, the cage 43 and the disk rotor 5 have a configuration in which the force for rotating the rolling element 42 by the disk rotor 5 is larger than the force for holding the rolling element 42 by the cage 43. Here, the brake device 1 includes a friction coefficient (dynamic friction coefficient) μ1 at a contact portion between the disk rotor 5 and the rolling element 42, a friction coefficient (dynamic friction coefficient) μ2 at a contact portion between the cage 43 and the rolling element 42, By setting the relationship between the normal β of the contact wall surface 43a at the contact portion of the cage 43 with the rolling element 42 and the angle β (see FIG. 1) formed by the pressing direction of the actuator 3 to satisfy a predetermined condition. The above configuration is realized. The angle β (0 ° <β <90 °) corresponds to the cone apex angle of the holding groove 43b.

  Here, the torque generated between the rolling element 42 and the disk rotor 5 is referred to as torque T1, and the torque generated between the rolling element 42 and the retainer 43 is referred to as torque T2. The torque T1 is a torque corresponding to a force that rotates the rolling element 42 by the disk rotor 5, and is a rotor imparting torque that is generated when the rolling element 42 is rotated by the disk rotor 5 that rotates together with the wheels. The torque T2 is a torque corresponding to the force that holds the rolling element 42 by the cage 43, in other words, the torque that stops the rolling element 42 by the cage 43, and rotates while the rolling element 42 is held by the cage 43. This is the cage braking torque generated by the operation. In the brake device 1, the torque T1 acting on the contact portion between the disc rotor 5 and the rolling element 42 exceeds the torque T2 acting on the contact portion between the retainer 43 and the rolling element 42, that is, T1> T2 is satisfied. Thus, the disk rotor 5 can rotate the rolling element 42 by the retainer 43 in accordance with the relative displacement between the brake pad 4 and the disk rotor 5. That is, the condition for the disc rotor 5 to rotate the rolling element 42 by the retainer 43 in accordance with the relative displacement between the brake pad 4 and the disc rotor 5 is to satisfy T1> T2.

  Then, the brake device 1 holds the retainer 43 so that the relationship between the friction coefficient μ1, the friction coefficient μ2, and the angle β satisfies the conditional expression expressed by the following formula (1) expressed by the following formula 1, for example. By setting the shape of the groove 43b, the friction coefficient of the outer surface of the rolling element 42, the friction coefficient of the contact wall surface 43a of the cage 43, the friction coefficient of the contact surface 5a of the disk rotor 5, the condition of T1> T2 is satisfied. Can be satisfied. That is, the cage 43 and the disk rotor 5 are formed in a shape in which the relationship among the friction coefficient μ1, the friction coefficient μ2, and the angle β satisfies the formula (1). Therefore, the brake device 1 realizes a configuration in which the torque T1 exceeds the torque T2 by setting the relationship among the friction coefficient μ1, the friction coefficient μ2, and the angle β so as to satisfy the condition of the above formula (1). be able to.

  Here, in the brake device 1, there is a possibility that the contact state may not be stabilized due to the minute unevenness of the surface on which the contact surface 5 a of the disk rotor 5 and the rolling element 42 come into contact and slide. Particularly, in the brake device 1, when the rolling element 42 and the disk rotor 5 are both made of a hard material as described above, the contact between the disk rotor 5 and the rolling element 42 becomes a contact between the hard materials. The tendency becomes remarkable, and the friction coefficient μ1 at the contact portion between the disk rotor 5 and the rolling element 42 is not stable, and the friction performance may not be stable.

  Therefore, as shown in FIGS. 1 and 2, the brake device 1 of the present embodiment is provided with a coating 48 on at least one of the contact surfaces between the rolling element 42 and the disk rotor 5, thereby stabilizing the friction coefficient. The friction performance is optimized.

  Specifically, the coating 48 is provided on one or both of the contact surface 42 a of the rolling element 42 and the contact surface 5 a of the disk rotor 5. The contact surface 42 a is a contact surface of the rolling element 42 with the disk rotor 5 and a sliding surface with the disk rotor 5. The contact surface 42a is a main body outer surface (outer surface) of the rolling element 42 formed of a hard material. On the other hand, the contact surface 5 a is a contact surface with the rolling element 42 of the disk rotor 5 and a sliding surface with the rolling element 42. The contact surface 5a is the surface of the disc rotor 5 formed of a hard material. The contact surface 5 a is a surface facing the rolling element 42 of the disk rotor 5. Here, the coating 48 is provided on the contact surface 42 a that is a contact surface of the rolling element 42 with the disk rotor 5, and coats the outer surface of the main body of the rolling element 42.

  The coating 48 is typically formed by various surface treatments such as injection molding, and is typically a material having relatively high heat resistance and durability that can withstand long-term use, such as a thermoplastic resin (for example, polyimide or the like). Super engineering plastic). The film thickness t of the film 48 is, for example, 0.1 [mm] or more, preferably 0.1 [mm] or more and 0.2 [mm] or less. That is, the film 48 is provided with a film thickness t in the range of 0.1 [mm] or more, preferably 0.1 [mm] or more and 0.2 [mm] or less. Yes.

  When the friction coefficient of the outer surface of the rolling element 42 is set so that the relationship between the friction coefficient μ1, the friction coefficient μ2, and the angle β satisfies the formula (1) as described above, the friction coefficient of the surface of the film 48 is set. May be treated as the friction coefficient of the outer surface of the rolling element 42.

  In the brake device 1 configured as described above, when the brake pad 4 is pressed against the rotating disk rotor 5, the rotation of the disk rotor 5 is transmitted to the rolling element 42, so that the rolling element 42 is held in the cage. Rotate at 43 (roll). That is, the brake device 1 can roll the rolling element 42 with the disc rotor 5 and cause the rolling element 42 to rub on the cage 43 side of the brake pad 4. The brake device 1 rotates while the rolling element 42 is held by the holder 43, so that the rolling element 42 and the holder 43 slide according to the rotation of the rolling element 42, and the rolling element 42 and the holder 43 A braking force that brakes the rotation of the disk rotor 5 can be generated by a friction force (friction resistance force) generated during When the brake pad 1 and the disc rotor 5 are pressed against each other, the brake device 1 rolls the rolling element 42 when the disc rotor 5 rolls the rolling element 42 with the relative displacement between the brake pad 4 and the disc rotor 5. The relative displacement can be braked by a frictional force generated between the cage 43 and the cage 43. As a result, the brake device 1 can apply a predetermined braking force to the disk rotor 5 and thus to the wheels. At this time, when the contact wall surface 43a is inclined according to the angle β as in the present embodiment, the brake device 1 is controlled when the surface shape of the contact surface with the rolling element 42 of the cage 43 is flat. Compared with power, for example, a braking force f about (1/2) · [(2β / sin2β) +1] times can be generated, and the braking performance can be relatively improved.

  As a result, the brake device 1 can suitably set performance such as friction performance and wear resistance performance regardless of the projected area of the surface of the brake pad 4 that is pressed against the disc rotor 5. That is, the brake device 1 includes the number of rolling elements 42, the shape of the holding groove 43b of the cage 43, the friction coefficient of the outer surface of the rolling element 42, the friction coefficient of the contact wall surface 43a of the cage 43, and the contact surface of the disc rotor 5. By appropriately adjusting the friction coefficient of 5a and the like, it is possible to appropriately change the performance such as the friction performance and the wear resistance performance regardless of the projected area of the brake pad 4 on the cage 43 side. The brake device 1, the brake device friction pair 2, and the brake pad 4 that do not depend on the projected area of the pad 4 on the cage 43 side can be realized.

  For example, the brake device 1 includes a configuration that brakes the rotation of the disk rotor 5 by a frictional force generated between the rolling element 42 and the retainer 43 when the disk rotor 5 rolls the rolling element 42. The area of the entire outer surface of the rolling element 42 can be the wear area of the brake pad 4. As a result, the brake device 1 can increase the wear area beyond the projected area (pad plane) of the brake pad 4 on the cage 43 side, and can improve wear resistance.

  Further, the brake device 1 includes a configuration that brakes the rotation of the disk rotor 5 by a frictional force generated between the rolling element 42 and the retainer 43 when the disk rotor 5 rolls the rolling element 42, for example, Compared with the case where the rotation of the disk rotor 5 is braked by friction between planes, the load at the friction contact point and the friction contact point is stabilized even when the contact portion 41 is made of a hard material. And the friction performance can be improved.

  As shown in FIG. 2, in the brake device 1, when the coating 48 is provided on the contact surface 42 a of the rolling element 42, there are extremely minute irregularities on the contact surface 5 a, the contact surface 42 a, and the like. Even so, the film 48 absorbs the unevenness, and the influence of the unevenness on the sliding surface can be mitigated. Thereby, the brake device 1 can suppress the contact state between the rolling element 42 and the disk rotor 5 from becoming unstable, and stabilize the friction coefficient μ1 of the contact portion between the disk rotor 5 and the rolling element 42. The friction performance can be stabilized. As a result, the brake device 1 can stabilize the load at each friction contact point, optimize the friction performance, and improve the stability of the friction performance.

  According to the brake device 1 according to the embodiment described above, the brake pad 4 having the rolling element 42 and the holder 43 that rotatably holds the rolling element 42 and the brake pad 42 provided in contact with the rolling element 42 are provided. A disk rotor 5 that rotates the rolling element 42 by the retainer 43 according to relative displacement with the pad 4 and an actuator 3 that presses the brake pad 4 and the disk rotor 5 are provided. The contact between the rolling element 42 and the disk rotor 5 A coating 48 is provided on at least one of the surfaces. According to the brake device friction couple 2 according to the embodiment described above, the brake pad 4 having the rolling element 42 and the holder 43 that rotatably holds the rolling element 42 and the rolling element 42 are brought into contact with each other. The disk rotor 5 is provided that rotates the rolling element 42 by the retainer 43 in accordance with the relative displacement with the brake pad 4, and a coating 48 is provided on at least one of the contact surfaces of the rolling element 42 and the disk rotor 5. According to the brake pad 4 according to the embodiment described above, the rolling element 42 and the holder 43 that rotatably holds the rolling element 42 are provided on the surface that is pressed against the disk rotor 5 that rotates together with the wheel. The coating 48 is provided on the contact surface of the rolling element 42 with the disk rotor 5. Therefore, the performance of the brake device 1, the brake device friction pair 2, and the brake pad 4 can be suitably set regardless of the projected area of the surface of the brake pad 4 that is pressed against the disk rotor 5. . The brake device 1, the brake device friction pair 2, and the brake pad 4 are provided with a coating 48 on the contact surface 42 a of the rolling element 42, so that the friction coefficient of the contact portion between the disc rotor 5 and the rolling element 42 is provided. μ1 can be stabilized and friction performance can be optimized.

  In addition, the brake device 1 uses a rolling element 42 made of a hard material as a part of the contact portion 41, so that, for example, a disc at the contact portion 41 is compared with a case where a general friction material is used. The melting point of the portion in contact with the rotor 5 can be made relatively high, whereby the allowable range for heat of the brake device friction pair 2 can be expanded.

  The brake device, the friction pair for brake device, and the brake pad according to the above-described embodiment of the present invention are not limited to the above-described embodiment, and various modifications can be made within the scope described in the claims. .

  In the above description, the coating 48 has been described as being provided on the rolling element 42, but may be provided on the contact surface 5 a that is a contact surface with the rolling element 42 of the disk rotor 5.

  The brake device 1 described above has been described on the assumption that the holding groove 43b is formed in a conical shape, but is not limited thereto, and may be a rectangular parallelepiped shape, a cubic shape, or a triangular prism shape.

  Moreover, although the brake device 1 demonstrated above demonstrated that the holder | retainer 43 had the holding groove 43b, a holding surface may be flat. In this case, the brake device 1 is configured so that the torque T1 exceeds the torque T2 by appropriately adjusting the friction coefficient between the rolling element 42 and the disk rotor 5 and the friction coefficient between the rolling element 42 and the retainer 43, and In other words, a configuration for rotating the rolling element 42 by the disk rotor 5 that rotates together with the wheel and friction of the rolling element 42 on the cage 43 side may be realized.

  Moreover, although the brake device 1 demonstrated above demonstrated the rolling element 42 as what was a spherical body, it is not restricted to this. As long as the rolling element 42 is rotatable in the direction of relative displacement between the brake pad 4 and the disk rotor 5, that is, in the rotation direction of the disk rotor 5, a barrel-shaped or spindle-shaped or cylindrical-shaped roller or needle It may be.

  In the above description, the brake pad 4 is the first member and the disc rotor 5 is the second member. However, the present invention is not limited to this, and the disc rotor is the first member and the brake pad is the second member. In other words, for example, the rolling element may be held by a holder provided on the disk rotor side. In this case, the rolling element is rolled by the brake pad in accordance with the relative displacement between the brake pad and the disk rotor, and a braking force is applied to the wheel by a frictional resistance force generated between the cage of the disk rotor and the rolling element. It becomes possible.

  As described above, the brake device, the brake device friction pair and the brake pad according to the present invention are suitable for application to various brake devices, brake device friction pairs and brake pads used in vehicles.

1 Brake Device 2 Friction Pair for Brake Device 3 Actuator (Pressing Mechanism)
4 Brake pads (first member)
5 Disc rotor (second member)
5a, 42a Contact surface (contact surface)
42 Rolling body 43 Cage 48 Film

Claims (9)

A first member having a rolling element and a cage that rotatably holds the rolling element;
A second member that is provided in contact with the rolling element and rotates the rolling element with the cage in accordance with a relative displacement with the first member;
A pressing mechanism for pressing the first member and the second member;
When the first member and the second member are pressed against each other, the second member rotates the rolling element with the relative displacement between the first member and the second member. Braking the relative displacement by frictional force generated between the cage and
A film is provided on at least one of the contact surfaces of the rolling element and the second member,
Brake device. The film is formed of a thermoplastic resin.
The brake device according to claim 1. The film is provided in a range where the film thickness is 0.1 [mm] or more.
The brake device according to claim 1 or 2. The coating is provided on a contact surface of the rolling element with the second member;
The brake device according to any one of claims 1 to 3. The rolling element is composed of a hard material,
The brake device according to any one of claims 1 to 4. The cage and the second member have a configuration in which a force for rotating the rolling element by the second member is larger than a force for holding the rolling element by the cage.
The brake device according to any one of claims 1 to 5. The first member is non-rotatable with the wheel;
The second member is rotatable with the wheel;
The brake device according to any one of claims 1 to 6. A first member having a rolling element and a cage that rotatably holds the rolling element;
A second member that is provided in contact with the rolling element and rotates the rolling element with the cage in accordance with a relative displacement with the first member;
When the first member and the second member are pressed against each other, the second member rotates the rolling element with the relative displacement between the first member and the second member. Braking the relative displacement by frictional force generated between the cage and
A film is provided on at least one of the contact surfaces of the rolling element and the second member,
Friction pair for brake equipment. On the surface that is pressed against the disk rotor that rotates together with the wheels, the rolling element and a holder that rotatably holds the rolling element,
The relative displacement is caused by a frictional force generated between the rolling element and the cage when the disk rotor rotates the rolling element in association with the relative displacement with the disk rotor while being pressed against the disk rotor. Brake
A film is provided on a contact surface of the rolling element with the disk rotor,
Brake pads.

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