Brake disc assembly

Abstract

The present invention is entitled "Brake Disc Assembly". The present invention discloses an article comprising a structural core, one or more friction pads and a plurality of elongated fasteners. The structural core comprises two core surfaces and a plurality of recesses extending between the core surfaces. Each friction pad comprises a pad surface and a friction surface opposite to the pad surface. Each pad surface comprises a flat pad surface and a plurality of bosses, the flat pad surface being configured to contact the core surface, the plurality of bosses extending from the first flat pad surface and comprising holes. Each flat pad surface is at least about 50% of the surface area of ​​the corresponding first pad surface and the corresponding second pad surface. The plurality of bosses engage with the plurality of recesses to position the corresponding first friction pad and the corresponding second friction pad relative to the structural core. The plurality of elongated fasteners pass through the holes of the corresponding bosses of the friction pads to fasten the friction pads to the structural core.

Description

Technical Field

[0001] The present disclosure relates to brake discs. Background Art

[0002] Aircraft braking systems may be used for various purposes, such as for slowing or stopping an aircraft while maneuvering on the ground. For example, when a jet-powered aircraft is landing, the aircraft braking system, various aerodynamic drag sources (e.g., fins, spoilers, etc.), and aircraft thrust reversers may be used to slow the aircraft down within a desired runway distance. Once the aircraft has sufficiently slowed down and is taxiing from the runway toward its ground destination, the aircraft braking system may be used to slow the aircraft down and stop it at its final ground destination. Summary of the invention

[0003] The present disclosure describes a brake disc assembly including a structural core and one or more friction pads. The friction pad includes a raised structure ("boss") that fits into and mechanically connects to an embedded structure ("pit") of the structural core and a pad surface that contacts and thermally connects to a core surface of the structural core. The friction pad can be configured to provide a friction surface for the brake disc assembly, while the structural core can be configured to provide strength for the brake disc assembly and remove heat from the friction pad.

[0004] In one example, the article includes a structural core, a first friction pad, a second friction pad, and a plurality of elongated fasteners. The structural core includes a first core surface, a second core surface, and a plurality of recesses extending between the first core surface and the second core surface. The first friction pad includes a first pad surface and a first friction surface opposite to the first pad surface. The first pad surface includes a first flat pad surface configured to contact the first core surface and a first plurality of bosses extending from the first flat pad surface, wherein each of the first plurality of bosses includes a first hole. Similarly, the second friction pad includes a second pad surface and a second friction surface opposite to the second pad surface. The second pad surface includes a second flat pad surface configured to contact the second core surface and a second plurality of bosses extending from the second flat pad surface, wherein each of the second plurality of bosses includes a second hole. Each elongated fastener is configured to pass through a first hole of a corresponding one of the first plurality of bosses and a second hole of a corresponding one of the second plurality of bosses to fasten the first friction pad and the second friction pad to the structural core. The first and second plurality of bosses are configured to engage the plurality of dimples to position the respective first and second friction pads relative to the structural core. Each of the first and second planar pad surfaces comprises at least about 50% of a surface area of ​​the respective first and second pad surfaces.

[0005] As another example, the method includes positioning a first plurality of bosses extending from a first flat pad surface of a first friction pad into a plurality of recesses extending between a first core surface and a second core surface of a structural core so that the first flat pad surface contacts the first core surface. The first friction pad includes a first pad surface and a first friction surface opposite to the first pad surface. Similarly, the method includes positioning a second plurality of bosses extending from a second flat pad surface of a second friction pad into a plurality of recesses extending between the first core surface and the second core surface of the structural core so that the second flat pad surface contacts the second core surface. The second friction pad includes a second pad surface and a second friction surface opposite to the second pad surface. The method also includes passing a plurality of elongated fasteners through a first hole of a corresponding one of the first plurality of bosses and a second hole of a corresponding one of the second plurality of bosses. The method also includes fixing the plurality of elongated fasteners to fasten the first friction pad and the second friction pad to the structural core.

[0006] As another example, a brake disc includes a structural core and a plurality of removable friction pads that can be attached to the structural core. One or more structural features of the structural core are configured to mate with one or more structural features of the plurality of removable friction pads. Therefore, the one or more structural features of the structural core and the one or more structural features of the plurality of removable friction pads are configured to transfer loads from the plurality of friction pads to the structural core. One or more surfaces of the structural core are configured to contact one or more surfaces of the plurality of removable friction pads. The structural core is configured to remove heat from the plurality of removable friction pads through the one or more surfaces of the plurality of removable friction pads.

[0007] The details of one or more examples of the present disclosure are set forth in the following drawings and the description. Other features, objects, and advantages of the present disclosure will be apparent from the description and drawings, and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a conceptual diagram illustrating an exemplary wheel and brake assembly that may include a brake disc assembly formed according to the techniques of this disclosure.

[0009] Figure 2A is a schematic front view of an example brake rotor assembly according to an example of the present disclosure.

[0010] Figure 2B is a schematic cross-sectional side view of an example brake rotor assembly according to an example of the present disclosure.

[0011] Figure 2C is a schematic cross-sectional side view of an exemplary structural core according to examples of the present disclosure.

[0012] Figure 2Dis a schematic cross-sectional side view of an exemplary friction pad according to an example of the present disclosure.

[0013] Figure 3 is a flow chart illustrating an exemplary technique for assembling a brake rotor assembly according to examples of the present disclosure. DETAILED DESCRIPTION

[0014] The present disclosure describes a brake rotor assembly that includes a structural core and one or more friction pads coupled to the structural core.

[0015] In an exemplary aircraft braking system, one or more rotatable brake discs ("rotors") may be mechanically connected to one or more wheels of the vehicle, and one or more stationary brake discs ("stators") may be mechanically connected to the body of the aircraft. The rotatable brake discs and the stationary brake discs may be alternately splined to the torque tube or wheel rim of the aircraft wheel to define a brake disc stack. To generate a desired braking force, a brake actuator may engage the rotatable brake disc and the stationary brake disc, which may engage each other. The friction between the brake discs converts the kinetic energy of the moving aircraft into heat energy, thereby slowing or stopping the aircraft.

[0016] According to the principles of the present disclosure, a brake disc includes a structural core and one or more friction pads. The structural core includes a plurality of recesses extending through the structural core. Each friction pad includes a plurality of raised bosses that fit into the recesses of the structural core and transfer at least a portion of the torque received by the friction pad during braking to the structural core. Each friction pad may also include a high proportion of the friction pad in contact with the structural core, such as greater than 50% of the total surface area, to transfer thermal energy to the structural core for dissipation. In a brake disc including opposing friction pads, the corresponding bosses of the opposing friction pads may be directly mated and secured using recessed fasteners that are subject to primarily tensile stresses. The material for the one or more friction pads may be selected for desired friction properties, while the material for the structural core may be selected for desired mechanical, corrosive and / or thermal properties.

[0017] Figure 1 1 is a conceptual diagram illustrating an exemplary wheel and brake assembly 10 according to an example of the present disclosure, which wheel and brake assembly may include one or more brake disc assemblies. For ease of description, examples of the present disclosure will be described primarily with respect to aircraft brake assemblies. However, the articles of the present disclosure may be used to form brake components other than aircraft brake discs. For example, the brake components may be used as friction materials in other types of braking applications and vehicles.

[0018] exist Figure 1In the example of FIG. 1 , the wheel and brake assembly 10 includes a wheel 12, an actuator assembly 14, a brake stack 16, and an axle 18. The wheel 12 includes a hub 20, a wheel leg flange 22, flange seals 24A and 24B, a lug bolt 26, and a lug nut 28. The actuator assembly 14 includes an actuator housing 30, an actuator housing bolt 32, and a plunger 34. The brake stack 16 includes alternating rotor brake discs 36 and stator brake discs 38; the rotor brake discs 36 are configured to move relative to the stator brake discs 38. The rotor brake discs 36 are mounted on the wheel 12, and in particular, the hub 20, by a beam key 40. The stator brake discs 38 are mounted to the axle 18 by a rack 44, and in particular, a torque tube 42. The wheel and brake assembly 10 can support any type of private, commercial, or military aircraft or other type of vehicle.

[0019] The wheel and brake assembly 10 includes a wheel 12 having a Figure 1 In the example of FIG. 1 , the wheel 12 is defined by a wheel hub 20 and a wheel leg flange 22. The wheel leg flange 22 may be mechanically secured to the wheel hub 20 by lug bolts 26 and lug nuts 28. The wheel 12 defines flange seals 24A and 24B. During assembly, an inflatable tire (not shown) may be placed over the wheel hub 20 and secured on the opposite side by the wheel leg flange 22. Thereafter, the lug nuts 28 may be tightened on the lug bolts 26, and the inflatable tire may be inflated with the flange seals 24A and 24B, thereby providing an airtight seal for the inflatable tire.

[0020] The wheel and brake assembly 10 may be mounted to the vehicle via the torque tube 42 and the shaft 18. Figure 1 In the example of FIG. 1 , the torque tube 42 is secured to the shaft 18 by a plurality of bolts 46. The torque tube 42 supports the actuator assembly 14 and the stator brake disc 38. The shaft 18 may be mounted on a stay of an undercarriage (not shown) or other suitable component of the vehicle to connect the wheel and brake assembly 10 to the vehicle.

[0021] During vehicle operation, braking may be required from time to time, such as during landing and taxiing procedures of an aircraft. The wheel and brake assembly 10 is configured to provide braking functions to the vehicle via an actuator assembly 14 and a brake stack 16. The actuator assembly 14 includes an actuator housing 30 and a plunger 34. The actuator assembly 14 may include different types of actuators, such as, for example, one or more of an electro-mechanical actuator, a hydraulic actuator, a pneumatic actuator, etc. During operation, the plunger 34 may extend away from the actuator housing 30 to axially compress the brake stack 16 against a compression point 48 for braking.

[0022] The brake stack 16 includes alternating rotor brake discs 36 and stator brake discs 38. The rotor brake discs 36 are mounted on the hub 20 for common rotation via beam keys 40. The stator brake discs 38 are mounted to a torque tube 42 via a rack 44. Figure 1 In the example of FIG. 1 , the brake stack 16 includes four rotors and five stators. However, in other examples, a different number of rotors and / or stators may be included in the brake stack 16 .

[0023] In some examples, the rotor brake disc 36 and the stator brake disc 38 may be mounted in the wheel and brake assembly 10 by beam keys 40 and racks 44, respectively. In some examples, the beam keys 40 may be spaced circumferentially around the inner portion of the hub 20. For example, the beam keys 40 may be shaped to have opposite ends (e.g., opposite sides of a rectangle), and may have one end mechanically fixed to the inner portion of the hub 20 and an opposite end mechanically fixed to the outer portion of the hub 20. The beam keys 40 may be integrally formed with the hub 20, or may be separate from the hub 20 and mechanically fixed to the hub 20, for example, to provide a thermal barrier between the rotor brake disc 36 and the hub 20. To this end, in various examples, the wheel and brake assembly 10 may include a heat shield (not shown) that extends radially outward and outwardly around the brake stack 16, for example, to limit heat transfer between the brake stack 16 and the wheel 12.

[0024] In some examples, the racks 44 may be spaced circumferentially around the outer portion of the torque tube 42. As such, the stator brake disc 38 may include a plurality of radially inwardly disposed lug slots along the inner diameter of the brake disc that are configured to engage with the racks 44. Similarly, the rotor brake disc 36 may include a plurality of radially inwardly disposed lug slots along the outer diameter of the brake disc that are configured to engage with the beam keys 40. As such, the rotor brake disc 36 will rotate with the movement of the wheel while the stator brake disc 38 remains stationary, allowing the friction surfaces of the adjacent stator brake discs 38 and rotor brake discs 36 to engage with each other, thereby decelerating the rotation of the wheel 12.

[0025] The rotor brake disc 36 and the stator brake disc 38 can provide relative friction surfaces for braking the aircraft. As the kinetic energy of the moving aircraft is converted into heat energy in the brake stack 16, the temperature in the brake stack 16 may rise rapidly. As such, the rotor brake disc 36 and the stator brake disc 38 forming the brake stack 16 may include a strong thermally stable material that can operate at very high temperatures and dissipate heat quickly. As torque is applied to the brake stack 16, the stress in the brake stack 16 may increase. As such, the rotor brake disc 36 and the stator brake disc 38 forming the brake stack 16 may include a high-strength corrosion-resistant material that can operate under very high stress. However, these thermal properties and structural properties may not be obtained in a single material. For example, a material with high thermal stability may not effectively transfer heat or provide high strength.

[0026] In some examples, at least one of rotor brake disks 36 and / or at least one of stator brake disks 38 is formed from a structural core and one or more friction pads on one or more sides of the structural core. Figure 2A is a schematic front view of an exemplary brake disc assembly 100 according to an example of the present disclosure, and Figure 2B According to the example of the present disclosure Figure 2A Schematic cross-sectional side view of an exemplary brake disc assembly 100. The brake disc assembly 100 includes a structural core 102 and a plurality of friction pads on one or more sides of the structural core 102. Figure 2A and Figure 2B In the example of FIG. 1 , the plurality of friction pads includes a first friction pad 104A and a second friction pad 104B (individually referred to as “friction pad 104 ” and collectively referred to as “plurality of friction pads 104 ”).

[0027] The brake disc assembly 100 may be used with any one or more of the rotor brake disc 36 and / or the stator brake disc 38. The brake disc assembly 100 may be used, for example, Figure 1 The rotor brake disc 36 or the stator brake disc 38 of the embodiment of the present invention. As used herein, "brake disc" and "brake disc assembly" are used interchangeably to describe either the rotor disc or the stator disc. Likewise, the terms "friction pad" and "structural core" are used to describe the friction pad and structural core of either the rotor disc or the stator disc, and are not intended to confer a geometric configuration specific to one or the other.

[0028] The structural core 102 may be a disk or annulus having a first core surface 124A and a second core surface 124B (individually referred to as "core surface 124" and collectively referred to as "core surfaces 124") that are oriented relative to each other and configured to receive and connect with corresponding friction pads 104A and 104B. Accordingly, each friction pad 104 may be a disk or annulus having corresponding pad surfaces 115A and 115B (individually referred to as "pad surfaces 115" and collectively referred to as "pad surfaces 115") oriented relative to each other and corresponding friction surfaces 112A and 112B (individually referred to as "friction surfaces 104" and collectively referred to as "friction surfaces 104"). Each pad surface 115 of the friction pad 104 is configured to be received by the structural core 102 and connected to a core surface 124 on the same side of the structural core 102 and a support structure, such as another friction pad 104 , on an opposite side of the structural core 102 .

[0029] By forming the structural core 102 and the friction pad 104 as separate components, the materials forming the components can be tailored to exhibit different mechanical, chemical, and / or thermal properties, such as improved friction properties of the friction pad 104 and improved strength, corrosion resistance, and / or heat transfer properties of the structural core 102. In addition, the structural core 102 and the friction pad 104 can include various structures and surface features that are configured to relieve stress and / or remove heat from the friction pad 104 to allow for further differentiation of material properties between the structural core 102 and the friction pad 104. The resulting brake disc assembly 100 can exhibit both improved strength within the underlying structural core 102 and improved friction performance associated with the friction pad 104.

[0030] The first core surface and the second core surface 124 of the structural core 102 may include one or more structural features configured to mate and connect with one or more friction pads 104. Correspondingly, the first pad surface and the second pad surface 115 of the friction pad 104 may include one or more structural features configured to mate and connect with the one or more structural features of the structural core 102. The structural features of the structural core 102 and the friction pad 104 may provide improved load distribution, better friction pad retention, reduced costs associated with manufacturing and assembly, and other benefits described in further detail below. The structural features of the structural core 102 may include, for example, one or more of geometrically complementary dimples 110 (shown in phantom) and corresponding bosses 116 for mating and distributing torque load forces between the structural core 102 and the corresponding friction pad 104.

[0031] The first and second core surfaces 124 of the structural core 102 may also include a high percentage of surface area that is configured to thermally contact the pad surface 115 of the friction pad 104. The first and second core surfaces 124 may thermally contact the friction pad 104 by being sufficiently close to the friction pad 104 so that the friction pad 104 transfers heat to the first and second core surfaces 124, such as by direct contact or through an intermediate layer or volumetric contact. Correspondingly, the first and second pad surfaces 115 of the friction pad 104 may include a high percentage of surface area that is configured to thermally contact the structural core 102. The high percentage of surface area of ​​the structural core 102 and the friction pad 104 in thermal contact may provide improved heat removal and dissipation (e.g., higher heat removal rates, lower temperatures, and / or more uniform temperature distribution) from the friction pad 104 to the structural core 102. The proportion of the surface area of ​​the friction pad 104 in thermal contact with the structural core 102 can be, for example, greater than 50% of the total surface area of ​​the pad surface 115 of the corresponding friction pad 104 facing the structural core 102, such as greater than 70% of the total surface area of ​​the pad surface 115, or greater than 90% of the total surface area of ​​the pad surface 115.

[0032] The friction pads 104 may include one or more securing features configured to secure opposing friction pads 104 to each other. The securing features of the friction pads 104 may provide improved installation and manufacturing convenience. The securing features of the friction pads 104 may include, for example, one or more holes 106 for extending between the friction pads 104 and securing fasteners 108.

[0033] The structural core 102 includes a first core surface 124A on a first side and a second core surface 124B on a second side. The structural core 102 also includes a plurality of dimples 110 extending between the first core surface 124A and the second core surface 124B. The first friction pad 104A includes a first friction surface 112A, a first planar pad surface 114A, and a first plurality of bosses 116A extending from the first planar pad surface 114A. The second friction pad 104B includes a second friction surface 112B, a second planar pad surface 114B, and a second plurality of bosses 116B extending axially outward (e.g., along an intended rotational axis of the structural core 102) from the second planar pad surface 114B. Each of the first plurality of bosses 116A includes a first hole 106A, and each of the second plurality of bosses 116B includes a second hole 106B.

[0034] like Figure 2BAs shown, when the brake disc assembly 100 is assembled, the first flat pad surface 114A contacts the first core surface 124A, and the second flat pad surface 114B contacts the second core surface 124B. The first plurality of bosses 116A and the second plurality of bosses 116B engage with the plurality of dimples 110 of the structural core 102 to position the corresponding first friction pad 104A and the second friction pad 104B relative to the structural core 102. One of the plurality of elongated fasteners 108 passes through the first hole 106A of a corresponding one of the first plurality of bosses 116A and the second hole 106B of a corresponding one of the second plurality of bosses 116B to fasten the first friction pad 104A and the second friction pad 104B to the structural core 102.

[0035] During braking, torque applied to the friction pad 104 and heat generated by the friction pad 104 can be transferred to the structural core 102. For example, the first friction surface 112A and the second friction surface 112B (individually referred to as "friction surface 112" and collectively referred to as "multiple friction surfaces 112") can receive torque from an adjacent friction surface and transfer at least a portion of the torque to the structural core 102 through the first plurality of bosses 116A and the second plurality of bosses 116B (individually referred to as "plurality of bosses 116" and collectively referred to as "plurality of bosses 116") of the friction pad 104 to the plurality of dimples 110 of the structural core 102. The friction surface 112 can also generate heat during braking and dissipate at least a portion of the heat from the core surface 124 of the structural core 102 to the structural core 102 to the first flat pad surface 114A and the second flat pad surface 114B (individually referred to as "flat pad surface 114" and collectively referred to as "plurality of flat pad surfaces 114") of the friction pad 104. The fasteners 108 securing the friction pads 104A and 104B may receive and transfer the tensile force to the opposing one of the friction pads 104 and, accordingly, the opposing core surface of the structural core 102. In this way, torque and heat generated during braking may be transferred from the friction pads 104 to the structural core 102, allowing the friction pads 104 to operate at lower stress and / or lower or more uniform temperatures than a disc brake assembly that does not include the structural and surface features of the disc brake assembly 100.

[0036] Figure 2C1 is a schematic cross-sectional side view of an exemplary structural core 102 according to an example of the present disclosure. The structural core 102 includes a first core surface 124A, a second core surface 124B, and a plurality of dimples 110 extending between the first core surface 124A and the second core surface 124B. The structural core 102 is configured to position a friction pad 104 relative to the structural core 102 using the plurality of dimples 110. Each of the plurality of dimples 110 is configured to engage with a boss of a plurality of bosses 116 of at least one friction pad 104 to position the corresponding friction pad 104 relative to the structural core 102. During attachment of the friction pad 104 to the structural core 102, the plurality of dimples 110 may receive the plurality of bosses 116 of at least one friction pad 104 so that the friction pad 104 may be quickly and / or easily positioned relative to the structural core 102.

[0037] The structural core 102 is configured to receive a braking force or torque from at least one friction pad 104 through a plurality of dimples 110. Each of the plurality of dimples 110 is configured to receive a boss of a plurality of bosses 116 of at least one friction pad 104 and includes a dimple wall 138 that intersects a plane of each core surface 124. During braking, at least a portion of the dimple wall 138 may receive a portion of the braking force from the boss of the corresponding friction pad 104. As such, the braking force may be distributed across the plurality of dimples 110. In some examples, each of the plurality of dimples 110 may be configured to receive a first boss (e.g., first boss 116A) from a first friction pad (e.g., first friction pad 104A) and a second boss (e.g., second boss 116B) from a second friction pad (e.g., second friction pad 104B) such that a surface of the first boss and a surface of the second boss may contact.

[0038] In addition to supporting the friction pads 104, the structural core 102 is also configured to receive thermal energy from at least one friction pad 104 through at least one of the core surfaces 124. Each core surface 124 can be configured to contact the flat pad surface 114 of at least one friction pad 104. The contact between the flat pad surface 114 of the respective friction pad 104 and the respective core surface 124 can provide thermal conduction of heat generated by the friction pad 104 to the respective core surface 124. In some examples, each core surface 124 can be configured such that at least 50% of the pad surface of the respective friction pad or combination of friction pads can contact the respective core surface 124. For example, each core surface 124 can have a shape and / or size such that substantially all of the pad surface of the respective friction pad that is not positioned in the plurality of dimples 110 can contact the respective core surface 124. In this way, heat can be removed more quickly and / or more evenly from the friction pads 104, such that the friction pads 104 can have a lower and / or more uniform temperature than friction pads that do not have a high surface area that contacts a structural member.

[0039] In some examples, the structural core 102 includes an edge 136 on the outer edge of the structural core 102. The edge 136 defines a first edge surface 126A that extends axially beyond the first core surface 124A and a second edge surface 126B that extends axially beyond the second core surface 124B. Although not shown, the edge 136 may include a drive area for coupling to the beam key. For example, the structural core 102 may be connected to the beam key via the drive area, rather than coupling the friction pad 104 to the beam key, so that the manufacture of the friction pad 104 may be less complicated. Additionally or alternatively, the edge 136 may be configured to increase the drive area that contacts the beam key, which may more effectively distribute the load to the beam key. In some examples, the edge 136 may be configured so that there is a gap between the outer edge of the corresponding friction pad and the inner radial surface of the edge 136. The gap can reduce vibrations generated as the friction pad wears by reducing the contact of the friction surfaces of the rotor and the stator with the outer diameter / inner diameter interface.

[0040] The structural core 102 may be a disk or annulus having a first core surface 124A and a second core surface 124B defining an inner diameter (ID) and an outer diameter (OD), the first core surface and the second core surface being oriented relative to each other and configured to receive the friction pad 104. The structural core 102 may have various dimensions (e.g., outer diameter, inner diameter, thickness, etc.), which may depend on its use (e.g., braking load). The thickness of the structural core 102 may depend on the strength and thermal aspects of the design of the structural core 102, as well as the material properties of the structural core 102. In some examples, the structural core 102 may have a thickness between the first core surface 124A and the second core surface 124B that is between about 0.125 inches and about 2 inches.

[0041] In some examples, the dimensions of the structural core 102 may be selected to provide improved thermal contact with the friction pad 104. For example, as the contact area between the surface of the structural core 102 and the friction pad 104 increases, the amount of thermal energy that can be transferred from the friction pad 104 to the structural core 102 increases due to a given temperature gradient between the structural core 102 and the friction pad 104. In some examples, the structural core 102 may have an inner diameter and an outer diameter such that substantially all (e.g., greater than 95%) of the planar pad surface 114 of the friction pad 104 may be in contact with one of the core surface 124A or the core surface 124B when the friction pad 104 is received on the corresponding core surface 124.

[0042] In some examples, the plurality of dimples 110 and correspondingly the plurality of bosses 116 may be configured such that the structural integrity of the structural core 102 and the friction pad 104 may be improved. For example, the plurality of bosses 116 and the plurality of dimples 110 may be sized to have an area parallel to the friction surface 112 to overcome the shear load stress applied to the plurality of bosses. As another example, the plurality of bosses 116 and the plurality of dimples may be sized such that the shear load on the structural core 102 may not exceed an integrity threshold. As such, the plurality of dimples 110 and the plurality of bosses 116 may be sized to strike a balance between the structural integrity of the structural core 102 and the structural integrity of the friction pad 104. As another example, the plurality of dimples 110 and the plurality of bosses 116 may have a thickness sufficient to overcome the bearing load stress.

[0043] The plurality of dimples 110 may be configured to have a size, orientation, and distribution based on a variety of factors, including, but not limited to, the surface area of ​​each dimple, the surface area of ​​the plurality of dimples, the ratio of the tangential surface area (e.g., the surface area of ​​each dimple in a direction tangential to the direction of rotation of the structural core 102) to the axial surface area, etc. In some examples, the size, shape, and location of the plurality of dimples 110 may be standardized so that a variety of friction pads 104 with different characteristics may be used with the structural core 102. For example, the service life of the structural core 102 may be significantly longer than the service life of the friction pad 104, so that the friction pad 104 may be replaced and, in some cases, updated with other friction pads 104. As another example, a universal friction pad 104 may be used with a variety of structural cores 102. For example, the structural core of a rotor having a drive region on the outer diameter may be slightly different from the structural core of a stator having a drive region on the inner diameter, but the rotor and stator may both use the same friction pad. Such cross-compatibility may reduce the number of designs of friction pads 104 used to form a brake.

[0044] The plurality of dimples 110 can have a variety of sizes and dimensions. In some examples, each dimple in the plurality of dimples has a circumferential dimension (e.g., measured from the center of each dimple along an arc of rotation parallel to the rotation direction of the structural core 102) between about 0.25 inches (such as for a large number of dimples 110 and / or friction pads 104) and about 12 inches (such as for a small number of dimples 110 and / or friction pads 104). In some examples, each dimple in the plurality of dimples has a radial dimension (e.g., measured from the center of each dimple along a radial direction of the center of the structural core 102) between about 0.25 inches and about 8 inches. The plurality of dimples 110 can have a variety of numbers. In some examples, the number of the plurality of dimples 110 is between 3 (such as for a design with a small number of friction pads 104 each having a high surface area) and 36 (such as for a design with a large number of friction pads 104 each having a low surface area).

[0045] The plurality of dimples 110 may have a variety of shapes in the radial plane, including but not limited to rectangular, rounded rectangular, circular, wedge-shaped, etc. In some examples, the plurality of dimples 110 may have a shape and orientation with a high tangential surface area. Figure 2A As shown, a braking force can be applied substantially tangential to the structural core 102, parallel to a major surface of the structural core (e.g., core surface 124A or core surface 124B). As such, dimples shaped and oriented so that dimple walls 138 have a high surface area facing the direction of the braking force can distribute the received force over a larger surface area.

[0046] The plurality of dimples 110 may have a variety of configurations and patterns. In some examples, the number and / or tangential surface area corresponds to the magnitude of the force received from the radial distance from the center of the structural core 102. In some examples, the plurality of dimples 110 may be symmetrical in at least one plane. In some examples, each dimple in the plurality of dimples 110 may be located at the same radial distance from the center of the structural core 102, such that each dimple in the plurality of dimples 110 may receive substantially the same torque. In some examples, the plurality of dimples 110 may be located at different radial distances from the center of the structural core 102.

[0047] The structural core 102 may be made of a variety of materials, including but not limited to metals, such as aluminum, stainless steel, and titanium alloys; carbon composites (e.g., carbon-carbon composites); etc. In some examples, the structural core 102 may be made of one or more materials that can be refurbished, so that the service life of the structural core 102 may be substantially longer than the friction pad 104.

[0048] In some examples, the structural core 102 can be made of a material having high strength, particularly in the circumferential direction. For example, as described above, the structural core 102 can be configured to receive braking forces from the friction pads 104. As such, the structural core 102 can be made of a material having high strength to withstand the various forces generated on the structural core due to the received braking forces. In some examples, the structural core 102 has high strength (tensile, compressive, and / or shear) at high temperatures experienced during braking.

[0049] In some examples, the structural core 102 may be made of a material having the ability to receive and / or store a large amount of heat. For example, as described above, the structural core 102 may be configured to receive heat from the friction pad 104. As such, the structural core 102 may be made of a material having a high specific heat capacity to receive a large amount of heat and / or other thermal properties such as a high heat dissipation rate or a high thermal diffusivity. In some examples, the structural core 102 includes a material having a specific heat capacity greater than 200 J / kg·K, such as greater than 475 J / kg·K at room temperature. For example, tungsten carbide may have a specific heat greater than 200 J / kg·K, steel may have a specific heat capacity greater than 475 J / kg·K, and boron nitride may have a specific heat capacity greater than 1500 J / kg·K. In some examples, the structural core 102 includes a material having a thermal conductivity greater than 7 W / m·K, such as greater than 20 W / m·K at room temperature. For example, a titanium alloy may have a thermal conductivity greater than 7 W / m·K. In some examples, structural core 102 includes a material having a thermal conductivity greater than carbon (approximately 23 W / m·K).

[0050] In some examples, the structural core 102 includes a carbon composite material. For example, the structural core 102 may be formed by a carbon-carbon composite material, which is made of a dense carbon material. In some examples, the carbon material may include a variety of carbon fibers and dense materials. The carbon fiber may be composed of carbon or a carbon precursor material such as polyacrylonitrile (PAN) or rayon, which may be converted into carbon by a carbonization process. The carbon fiber used to form the core structure 102 may be arranged in a woven or non-woven fabric as any one of a single layer or multilayer structure. In some examples where both the structural core 102 and the friction pad 104 are carbon composites, the structural core 102 and / or the friction pad 104 may include the same underlying carbon structure (e.g., both are woven), or may include different carbon fiber structures (e.g., woven core structures and non-woven friction pads) according to the desired mechanical or friction properties. In some examples, a carbon-carbon composite material customized for improved strength may include woven carbon fibers and reinforcing materials (e.g., carbonized asphalt or resin). The woven structure of the carbon fiber matrix may improve the resulting strength properties of the structural core 102 as compared to a non-woven structure.

[0051] In some examples, the structural core 102 can be manufactured by relatively simple manufacturing processes such as cutting (e.g., milling, drilling) and casting (e.g., die casting) processes. For example, structural features of the structural core 102, such as the plurality of dimples 110 and the edges 136, can involve relatively simple geometries (e.g., substantially square angles between the core surface 124 and the dimple walls 138) that are relatively simple to manufacture. As such, standard machining and manufacturing processes applicable to these simple geometries can be used to more quickly and / or inexpensively manufacture the structural core 102. Additionally or alternatively, such simple geometries can allow for easier refurbishment or repair of the structural core 102, such that the useful life of the structural core 102 can be more easily and / or inexpensively extended.

[0052] Figure 2D is a schematic cross-sectional side view of an exemplary friction pad 104 according to an example of the present disclosure. The friction pad 104 includes a pad surface 115 and a friction surface 112 opposite the pad surface 115. The pad surface 115 includes a flat pad surface 114 and a boss surface 118 of each boss of a plurality of bosses 116 extending from the flat pad surface 114. The flat pad surface 114 is configured to contact and thermally interface with one of the core surfaces 124.

[0053] Each boss of the plurality of bosses 116 is configured to engage with a recess of the plurality of recesses 110 of the structural core 102 to position the corresponding friction pad 104 relative to the structural core 102. For example, each boss of the plurality of bosses 116 may have a size or shape that is complementary to a recess of the plurality of recesses 110. During attachment of the friction pad 104 to the structural core 102, the plurality of bosses 116 may fit into the plurality of recesses 110 of the structural core 102 so that the friction pad 104 may be quickly and / or easily positioned relative to the structural core 102.

[0054] The friction pad 104 is configured to transfer a braking force or torque to the structural core 102 through the plurality of bosses 116. Each boss of the plurality of bosses 116 is configured to be received by a dimple of the plurality of dimples 110 of the structural core 102 and includes a boss wall 134 that intersects the plane of the flat pad surface 114. During braking, at least a portion of the boss wall 134 is configured to contact at least a portion of a corresponding dimple wall 138 when the plurality of bosses 116 engage the plurality of dimples 110, such that at least a portion of the boss wall 134 can transfer a portion of the braking force to the dimples of the structural core 102. In this way, a braking force can be applied to the structural core 102 through the surface area of ​​the boss wall 134 of the plurality of bosses 116.

[0055] In addition to transferring braking forces, the friction pad 104 is also configured to convert kinetic energy into thermal energy and transfer at least a portion of the thermal energy to the structural core 102 through the pad surface 114. The flat pad surface 114 is configured to contact a core surface 124 of the structural core 102. The contact between the core surface 124 and the flat pad surface 114 can provide thermal conduction of heat generated by the friction surface 112 of the friction pad 104 to the corresponding core surface 124. In some examples, the thermal contact between the structural core 102 and the friction pad 104 can be expressed as a portion (e.g., a percentage) of the total surface area of ​​the friction pad 104 that is configured to contact the structural core 102 (e.g., the flat pad surface 114). The flat pad surface 114 includes at least about 50% of the surface area of ​​the pad surface 115. In some examples, the flat pad surface 114 includes at least about 70%, such as at least about 95%, of the surface area of ​​the pad surface 115.

[0056] The friction pad 104 is configured to be secured to the structural core 102 using fasteners such as fastener 108. Each of the plurality of bosses 116 includes a hole 106. The hole 106 is configured to receive the fastener 108 and pass the fastener 108 through to reach a structure on the opposite side of the structural core 102, such as another friction pad 104 in a two-side disc brake in the middle of the brake disc stack 16 or a support structure in a one-side disc brake at the end of the brake disc stack 16.

[0057] In some examples, the friction pad 104 can be configured to have an increased usable depth of the friction surface 112 over the life of the friction pad 104 by recessing the hole 106. For example, the depth of the friction surface 112 can be limited by a closer core surface 124 of the structural core 102 (e.g., closer to the friction surface 112) or by the fastener 108 in the hole 106, so that by recessing the hole 106, the fastener 108 may not limit the depth of the friction surface 112. In some examples, the inner hole surface 122 of each hole 106 extends a recessed distance 128 beyond the plane of the flat pad surface 114. In some examples, the recessed distance 128 is greater than the head height of the fastener 108, such as greater than about 0.1 inches. During use, the friction surface 112 of the friction pad 104 may not wear the fastener 108, so that the friction pad 104 can remain fixed to the structural core 102. In some examples, a thickness 132 of edge 136 between edge surface 126 and planar core surface 124 is approximately a thickness 130 of friction pad 104 between friction surface 112 and planar pad surface 114 , where thickness 130 represents a usable depth of friction surface 112 over the life of friction pad 104 .

[0058] The friction pad 104 may be in the shape of a disk or annulus defining a preformed outer diameter (OD) and a preformed inner diameter (ID). In some examples, the outer diameter (OD) of the friction pad 104 may be about 12 inches (e.g., about 37 cm) to about 25 inches (e.g., about 64 cm), and the preformed inner diameter (ID) of the friction pad 104 may be about 4.5 inches (e.g., about 12 cm) to about 15 inches (e.g., about 38 cm).

[0059] The plurality of bosses 116 may be configured to have a size, orientation, and distribution based on a variety of factors, including, but not limited to, thermal expansion of the bosses and / or dimples, bearing area of ​​the bosses and / or dimples, shear area of ​​the bosses and / or dimples, surface area of ​​each dimple, surface area of ​​the plurality of dimples, ratio of tangential surface area (e.g., surface area of ​​each boss in a direction tangential to the direction of rotation of the friction pad 104 ) to axial surface area, etc. The plurality of bosses 116 may have a size, orientation, or distribution that is complementary to the plurality of dimples 110 .

[0060] The plurality of bosses 116 can have a variety of sizes and dimensions. In some examples, each of the plurality of bosses 116 has a circumferential dimension between about 0.25 inches and about 12 inches (e.g., measured from the center of each boss along an arc of rotation parallel to the rotation direction of the friction pad 104). In some examples, each of the plurality of bosses 116 has a radial dimension between about 0.25 inches and about 8 inches (e.g., measured from the center of each dimple in a radial direction from the center of the friction pad 104).

[0061] The plurality of bosses 116 may have a variety of shapes corresponding to the shapes of the plurality of dimples 110 of the structural core 102, including but not limited to rectangular, rounded rectangular, circular, wedge-shaped, etc. In some examples, the plurality of bosses 116 may have a shape and orientation with a high tangential surface area. For example, Figure 2A As shown, a braking force substantially tangential to the structural core 102 may be applied. As such, a boss shaped and oriented such that the boss wall 134 has a high surface area facing the direction of the braking force may transfer the force to a larger surface area. In some examples, each boss surface 118 is configured to contact a corresponding boss surface 118 of another boss in the second plurality of bosses of another friction pad when the plurality of bosses 116 and the second plurality of bosses engage the plurality of dimples 110. As such, the plurality of bosses of two opposing friction pads may extend through the corresponding dimples 110 and contact substantially the entire inner surface of the corresponding dimples 110.

[0062] The plurality of bosses 116 may have a variety of configurations and patterns. In some examples, the number and / or tangential surface area corresponds to the amount of force received from the radial distance from the center of the friction pad 104. In some examples, the plurality of dimples 116 may be symmetrical in at least one plane. In some examples, the plurality of dimples 116 may have the same radial distance from the center of the friction pad 104, so that each of the plurality of bosses 116 may transfer substantially the same torque. In some examples, the plurality of bosses 116 may have different radial distances from the center of the friction pad 104.

[0063] In some examples, the friction pads 104 may be cross-compatible with both rotor brake discs and stator brake discs. For example, the rotor, stator, and end plate may use the same friction pads 104 attached to different styles of structural cores 102. As long as the plurality of dimples 110 of each structural core 102 for the stator, rotor, or end plate corresponds to the plurality of dimples 116 of the friction pads 104, such friction pads may be used with the corresponding structural cores 102, even though the design of the other parts of the structural cores 102 is different. Such cross-compatibility may reduce the number of parts to be manufactured, which may reduce inventory and allow for cheaper manufacturing.

[0064] The friction pad 104 may be made of a variety of materials, including but not limited to ceramics; metals or metal-containing materials; carbon composites; etc. In some examples, the friction pad 104 may be made of a material having high thermal stability, high wear resistance, and / or stable friction characteristics. For example, as described above, the friction pad 104 is configured to convert kinetic energy into thermal energy. As such, the friction pad 104 may be made of a material having high thermal stability to withstand high temperatures. In some examples, the friction pad 104 includes a material having an operating temperature threshold greater than about 1100°C, such as greater than about 1700°C. For example, carbon can withstand operating temperatures greater than about 1725°C.

[0065] In some examples, the friction pad 104 includes a carbon composite material. For example, the friction pad 104 may be formed by a carbon-carbon composite material, which is made of a dense carbon material. In some examples, the carbon material may include a variety of carbon fibers and dense materials. The carbon fiber may be composed of carbon or a carbon precursor material such as polyacrylonitrile (PAN) or rayon, which may be converted into carbon by a carbonization process. The carbon fiber used to form the friction pad 104 may be arranged in a woven or nonwoven fabric as either a single layer or a multilayer structure. In some examples, a carbon-carbon composite material customized for improved friction aspects may include non-woven carbon fibers and reinforcing materials (e.g., carbonized asphalt or resin). Compared with a woven structure, a non-woven structure of a carbon fiber matrix may improve the resulting friction characteristics of the friction pad 104.

[0066] Figure 3is a flow chart illustrating an example technique for assembling an example brake rotor assembly 100 according to an example of the present disclosure. Figure 3 Reference FIG. 2A to FIG. 2D However, it should be understood that Figure 3 The technology can be used to assemble other products. Figure 3 The technique includes positioning a first plurality of bosses 116A of a first friction pad 104A into a plurality of dimples 110 of a structural core 102 such that a first planar pad surface 114A contacts a first core surface 124A, and positioning a second plurality of bosses 116B of a second friction pad 104B into a plurality of dimples 110 of a structural core 102 such that a second planar pad surface 114B contacts a second core surface 124B. Figure 3 The technique also includes passing the plurality of elongated fasteners 108 through the first holes 106A of a corresponding one of the first plurality of bosses 116A and the second holes 106B of a corresponding one of the second plurality of bosses 116B. Figure 3 The technique also includes securing a plurality of elongated fasteners 108 to fasten the first friction pad 104A and the second friction pad 104B to the structural core 102 .

[0067] Various examples have been described. These and other examples are within the scope of the following claims.

Claims

1. A product comprising: a structural core comprising a first core surface, a second core surface, and a plurality of dimples extending between the first core surface and the second core surface; A first friction pad, the first friction pad comprising a first pad surface and a first friction surface opposite to the first pad surface, wherein the first pad surface comprises: a first planar pad surface configured to contact the first core surface; and a first plurality of bosses extending from the first planar pad surface, wherein each of the first plurality of bosses includes a first aperture; A second friction pad, the second friction pad comprising a second pad surface and a second friction surface opposite to the second pad surface, wherein the second pad surface comprises: a second planar pad surface configured to contact the second core surface; and a second plurality of bosses extending from the second planar pad surface, wherein each of the second plurality of bosses includes a second aperture; and a plurality of elongated fasteners, each elongated fastener being configured to pass through the first hole of a corresponding one of the first plurality of bosses and the second hole of a corresponding one of the second plurality of bosses to fasten the first friction pad and the second friction pad to the structural core, and each elongated fastener having a head height, wherein the first plurality of bosses and the second plurality of bosses are configured to engage with the plurality of dimples to position the respective first friction pad and the respective second friction pad relative to the structural core, wherein each of the first planar pad surface and the second planar pad surface comprises at least 50% of the surface area of ​​the respective first pad surface and the respective second pad surface, and wherein an inner bore surface of each of the first and second bores extends beyond the plane of the respective first and second planar pad surfaces by a recessed distance greater than a head height of the respective elongated fastener.

2. The product according to claim 1, Wherein the structural core further comprises an edge defining an edge surface extending axially beyond the core surface, and wherein a thickness of the edge between the edge surface and the core surface is approximately a thickness of the friction pad between the friction surface and the planar pad surface.

3. The article of claim 1 , wherein each of the first plurality of bosses and the second plurality of bosses is configured to fit within a corresponding one of the plurality of pockets in order to engage with the plurality of pockets to position the respective first friction pad and the respective second friction pad relative to the structural core.

4. The article of claim 1, wherein each of the first planar pad surface and the second planar pad surface comprises at least 90% of the surface area of ​​the respective first pad surface and the respective second pad surface.

5. The product according to claim 1, wherein each boss of the first plurality of bosses includes a first boss surface, wherein each boss of the second plurality of bosses includes a second boss surface, and wherein each first boss surface is configured to contact a corresponding second boss surface when the first plurality of bosses and the second plurality of bosses engage the plurality of dimples, and wherein each boss of the first plurality of bosses comprises a first boss wall, wherein each boss of the second plurality of bosses comprises a second boss wall, wherein each dimple of the plurality of dimples comprises a dimple wall, and wherein at least a portion of each first boss wall and second boss wall is configured to contact at least a portion of a corresponding dimple wall when the first plurality of bosses and the second plurality of bosses engage the plurality of dimples.

6. The product according to claim 1, wherein the structural core comprises at least one of a metal or a carbon / carbon composite material, and The structural core comprises a material having a specific heat capacity greater than 200 J / kg·K or a material having a thermal conductivity greater than 7 W / m·K.

7. The article of claim 1 or claim 6, wherein the first friction pad and the second friction pad comprise a material having an operating temperature threshold greater than 1100°C.

8. A method comprising: positioning a first plurality of projections extending from a first planar pad surface of a first friction pad into a plurality of dimples extending between a first core surface and a second core surface of a structural core to bring the first planar pad surface into contact with the first core surface, wherein the first friction pad includes a first pad surface and a first friction surface opposite the first pad surface; positioning a second plurality of projections extending from a second planar pad surface of a second friction pad into the plurality of dimples extending between the first core surface and the second core surface of the structural core so that the second planar pad surface contacts the second core surface, wherein the second friction pad includes a second pad surface and a second friction surface opposite the second pad surface; passing a plurality of elongated fasteners through the first aperture of a corresponding one of the first plurality of bosses and the second aperture of a corresponding one of the second plurality of bosses, each elongated fastener having a head height; as well as The plurality of elongated fasteners are secured to fasten the first friction pad and the second friction pad to the structural core, wherein an inner hole surface of each of the first and second holes extends beyond the plane of the corresponding first and second planar pad surfaces by a recessed distance greater than a head height of the corresponding elongated fastener.

9. A brake disc comprising: Structural core; and a plurality of removable friction pads attachable to the structural core, wherein the one or more structural features of the structural core are configured to mate with one or more structural features of the plurality of removable friction pads, wherein the one or more structural features of the structural core and the one or more structural features of the plurality of removable friction pads are configured to transfer loads from the plurality of friction pads to the structural core, wherein one or more surfaces of the structural core are configured to contact one or more surfaces of the plurality of removable friction pads, and wherein the structural core is configured to remove heat from the plurality of removable friction pads through the one or more surfaces of the plurality of removable friction pads, wherein the one or more structural features of the plurality of removable friction pads are configured to completely contain a plurality of elongated fasteners such that the plurality of elongated fasteners do not extend beyond the one or more surfaces of the structural core, and wherein each of the plurality of elongated fasteners has a head height greater than 0.1 inches.

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