Brake system return mechanism

Abstract

A brake system includes: (a) a caliper housing (22) supporting a brake pad assembly (24) associated with a piston; (b) a motor gear unit (40) having a motor connected to a drive gear (64), where the drive gear (64) moves the brake pad assembly based on power received by the motor during a brake application operation or a brake release operation; and (c) a plate (74) associated with the drive gear (40) wherein the plate (74) generates a reverse drive force to move the drive gear (40) during the brake release operation and in turn directly or indirectly move the brake pad assembly.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority to U.S. Provisional Application No. 63 / 420,232, filed Oct. 28, 2022, which is hereby incorporated by reference in its entirety. Technical Field

[0003] This teaching generally relates to a braking system, and more particularly, to a return mechanism for retracting brake pads of a braking system. Background Art

[0004] Various braking systems are used in a large number of vehicle and / or transportation applications. These braking systems can include one or more pistons, floating brake caliper housings or opposed piston (or fixed) brake caliper housings, or combinations thereof. Typically, these braking systems will also include rotary - to - linear actuators, such as ball - and - nut assemblies (BNAs).

[0005] A BNA can be powered by an electric motor directly or indirectly connected to the BNA. For example, one or more gears can be used to amplify and / or transfer torque from the electric motor to the BNA to drive the BNA. During brake application, the BNA can receive power, and at least a portion of the BNA (e.g., the spindle) can rotate. This rotation can then be converted into linear motion through one or more stages in the BNA to drive a piston toward one or more brake pads or brake shoes, thereby creating a clamping force between the one or more brake pads and a rotor or drum.

[0006] Typically, once the brake application operation is complete, the electric motor can release the contact between the piston and one or more brake pads or brake shoes. To do this, the electric motor can move the BNA and any intermediate gears in a direction opposite to the brake application direction. Advantageously, the BNA can also help release the piston by providing a reverse drive torque itself to reduce the torque required for the electric motor to release the piston. This reverse drive is possible due to one or more characteristics of the BNA.

[0007] However, in the case of a motor failure, such as the motor being unable to transfer the necessary torque in the application and / or release direction (e.g., a power failure to the motor), the motor may not be able to provide any torque in the opposite direction to release the piston from contact with one or more brake pads or brake shoes. Thus, the reverse drive provided only by the BNA can be used to release the piston. Unfortunately, this reverse drive may generally not be sufficient to fully release the brake application (i.e., clamping) force. That is, a portion of the applied force can remain unreleased.

[0008] To ensure that during a motor failure, the brake application force is fully released to minimize or eliminate contact between the piston and one or more brake pads or shoes, the BNA can be designed to provide sufficient or improved backdriving. For example, the BNA can be designed to increase backdriving to overcome the lack of torque provided by the failed motor. However, in various situations and configurations, it may be impractical or impossible to increase the backdriving of the BNA to fully release the brake application force. Thus, after a release operation is initiated, a portion of the brake application force may still be present, thereby maintaining contact between the piston and one or more brake pads or shoes. This contact can then result in contact (e.g., drag) between one or more brake pads or shoes and the rotor or drum. Unfortunately, the drag may then cause deterioration of the rotor or drum, the braking system, or both.

[0009] Accordingly, a braking system that allows the piston to fully release after a brake application operation during a motor failure would be attractive. What is needed is a braking system that includes an additional return mechanism that can assist in releasing the piston from contact with one or more brake pads or shoes. Additionally, a braking system that includes a return mechanism that can work with the BNA to move the piston in the release direction would be attractive. What is needed is a return mechanism connected to the BNA that, in addition to the backdriving generated by the BNA, also increases the torque in the release direction. Additionally, a braking system that increases the total backdriving to reduce the load on the motor during a release operation would be attractive. Accordingly, what is needed is a braking system with a return mechanism that improves the overall backdriving to increase the life of the motor due to the reduced load during a release operation. Summary of the Invention

[0010] This teaching meets one or more of these needs by providing a braking system including: (a) a brake caliper housing that supports a brake pad assembly connected to a piston; (b) an electric motor gear unit having an electric motor connected to a drive gear, wherein during a brake application operation or a brake release operation, the drive gear moves the brake pad assembly based on power received by the electric motor; and (c) a plate connected to the drive gear, wherein the plate generates a backdriving force to move the drive gear during the brake release operation and thereby directly or indirectly move the brake pad assembly.

[0011] When a motor failure occurs, the reverse driving force generated by the plate can be sufficient to retract the brake pad assembly from the vehicle's rotor to reduce or eliminate the force applied by the brake pad assembly to the rotor. The plate can be adapted to rotate with the drive gear during the brake application operation, the brake release operation, or both. The plate can also be adapted to rotate independently of the drive gear during the brake application operation, the brake release operation, or both, or vice versa. Additionally, the plate and the drive gear can be coaxial.

[0012] The drive gear can include a plurality of pins or protrusions extending from the surface of the drive gear, and the plurality of pins or protrusions interact with one or more fins extending from the surface of the plate. The plurality of pins can contact the one or more fins during the brake application operation, the brake release operation, or both, such that rotation of the drive gear causes rotation of the plate.

[0013] Furthermore, the plate can include a biasing member, and the biasing member can be wound during the brake application operation such that during the brake release operation, the biasing member releases the reverse driving force to move the drive gear. The biasing member can include a first arm fixed by a protrusion of the plate and a second arm that moves freely between a pair of stop points. The first stop point can be the initial position of the second arm before the biasing member is wound, and the second stop point can be the final position reached by the second arm when the biasing member has been fully wound. When the second arm reaches the second stop point during the brake application operation, the plurality of pins of the drive gear can deflect the one or more fins of the plate, thereby allowing the drive gear to continue rotating independently of the plate.

[0014] The biasing member can be fixed around the axis of the plate. The biasing member can be located on the surface of the plate opposite the surface that includes the one or more fins. Additionally, during the brake release operation, releasing the reverse driving force by the biasing member can cause the one or more fins of the plate to rotate and contact the plurality of pins of the drive gear, thereby causing the drive gear to also rotate in the same direction as the plate.

[0015] The braking system may include a gear train between the electric motor and the drive gear, and the torque generated by the electric motor may be transmitted to the drive gear through the gear train. Additionally, the electric motor may include an electric motor output end connected to the gear train, and the axis of rotation of the electric motor output end may be parallel or perpendicular to the axis of rotation of the drive gear. Further, the drive gear may be connected to a ball and nut assembly such that during the brake application operation, the drive gear may drive the ball and nut assembly to contact the piston, whereby the piston may contact the brake pad assembly to move the brake pad assembly toward the rotor of the vehicle.

[0016] Moreover, the shaft of the plate may be fixed to the housing of the electric motor gear unit by a clip. The pair of stop points of the biasing member may be protrusions located on the housing of the electric motor gear unit. Additionally, the drive gear may include an output shaft extending from the surface of the drive gear, the output shaft outputting the power received by the electric motor to move the brake pad assembly, and the plate may be positioned adjacent to the opposite surface of the drive gear.

[0017] The present teachings meet one or more of the present needs by providing: a braking system that allows for sufficient release of the piston after a brake application operation during an electric motor failure; a braking system that includes an additional return mechanism that may assist in releasing the piston from contact with one or more brake pads or brake shoes; a braking system that includes a return mechanism that may work with the BNA to move the piston in the release direction; a return mechanism that is connected to the BNA and that increases the torque in the release direction in addition to the reverse drive generated by the BNA; a braking system that increases the total reverse drive to reduce the load on the electric motor during a release operation; a braking system that has a return mechanism that increases the overall reverse drive to increase the life of the electric motor due to the reduced load during a release operation; or a combination thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a perspective view of the braking system.

[0019] Figure 2 is a perspective view of the braking system with the electric motor gear unit (MGU) housing removed.

[0020] Figure 3 is a cross-sectional view of the braking system according to the present teachings.

[0021] Figure 4Is an isometric view of a drive gear connected to the gear train of a braking system according to the present teachings.

[0022] Figure 5 Is an isometric view of a motor gear unit (MGU) housing according to the present teachings.

[0023] Figure 6 Is an isometric view of a drive gear connected to a plate according to the present teachings.

[0024] Figure 7 Is an isometric view of a drive gear connected to a plate according to the present teachings.

[0025] Figure 8 Is an isometric view of a drive gear connected to a plate according to the present teachings.

[0026] Figure 9 Is an isometric view of a drive gear connected to a plate according to the present teachings.

[0027] Figure 10 Is an isometric view of a drive gear connected to a plate according to the present teachings.

[0028] Figure 11 Is an isometric view of a drive gear according to the present teachings.

[0029] Figure 12 Is an isometric view of a plate connected to a motor gear unit (MGU) housing according to the present teachings. Detailed Description

[0030] The explanations and illustrations given herein are intended to acquaint other technicians in the field with the teachings, its principles, and its practical applications. Those skilled in the art can adapt and apply the teachings in many forms most suited to the requirements of a particular use. Accordingly, the specific embodiments of the teachings set forth herein are not intended to be exhaustive or limiting of the teachings. Thus, the scope of the teachings should not be determined with reference to the description herein, but rather should be determined with reference to the appended claims and the full scope of the equivalents to which such claims are entitled. The disclosures of all articles and references (including patent applications and publications) are incorporated by reference in their entirety for all purposes. Other combinations are possible, as will be gathered from the appended claims, which are also incorporated by reference in their entirety into this written description.

[0031] The present teachings generally relate to a braking system. The braking system can be a system or component for generating a clamping force during a braking application operation. The braking system can be any system or component for releasing the clamping force. The braking system can be used, configured to, or adapted or capable of generating a clamping force to decelerate, stop, and / or hold a vehicle in a stopped position. The clamping force can be used to decelerate, stop, and / or hold a vehicle in a stopped position during a service braking operation. The clamping force can be used to hold a vehicle in a stopped or parked position during a parking braking operation. The clamping force can be used during service and parking brake operations. The braking system can have hydraulic components, where hydraulic fluid is used to move brake pistons and brake pads against a braking surface (i.e., a brake rotor) to generate a clamping force during service and / or parking braking operations. The hydraulic components can be applied together with or separately from the torque distribution assembly disclosed herein.

[0032] The braking system can be an opposed braking system (i.e., a fixed caliper braking system) or a floating braking system (i.e., a floating caliper). The braking system can be a disc braking system. The braking system can be a drum braking system. The braking system can be a service braking system. The braking system can be a parking braking system.

[0033] The clamping force can be a force for decelerating, slowing down, stopping, and / or preventing the movement or rotation of a brake rotor, brake drum, and / or vehicle when frictionally coupled with a brake pad or brake shoe coefficient. The clamping force can be generated during a standard braking application (i.e., a braking application force). The clamping force can be generated during a parking braking application (i.e., a parking braking force).

[0034] The braking system can include one or more brake pad assemblies and a brake caliper housing that at least partially supports the one or more brake pad assemblies. During a braking application operation, one or more pistons located within or supported by the brake caliper housing can be moved toward and away from one or more brake pads by pressurizing brake fluid. Additionally or alternatively, during a braking application operation, one or more pistons and one or more brake pad assemblies can be moved together with an electromechanical element to generate a clamping force. Such electromechanical elements can include a rotary-to-linear mechanism, a spindle, a nut, an electric motor, one or more gears, a torque distribution assembly, a plate with a biasing member, or a combination thereof.

[0035] The brake rotor can cooperate with components of the braking system to generate a clamping force. The brake rotor can include an inner side and an opposite outer side. The brake caliper housing can be arranged such that: one or more brake pads are located on the inner side of the brake rotor (i.e., an inner brake pad), and one or more brake pads are located on the outer side of the brake rotor (i.e., an outer brake pad), or both.

[0036] The brake caliper housing may include one or more piston housings. The piston housing may define a hollow region within the brake caliper housing that is configured to receive and support a corresponding brake piston. The piston housing may be entirely located on one side (i.e., inner or outer) of the brake rotor, or on both sides of the brake rotor.

[0037] The brake system may have one or more pistons. The pistons may be used to move a brake pad assembly or corresponding ends of the brake pad assembly toward the brake rotor to generate a clamping force during a brake application operation. The pistons may be located on one side (i.e., inner or outer) of the brake rotor, or one or more pistons may be located on each side of the brake rotor.

[0038] During a brake application operation, to decelerate, slow down, stop, or hold a vehicle in a stopped or parked position, the brake piston may be moved by pressurizing a fluid (such as brake fluid). To release the clamping force or brake application, the brake piston may be moved by depressurizing the fluid. During a brake application, to decelerate, slow down, stop, or hold a vehicle in a stopped or parked position, the brake piston may move with one or more electromechanical mechanisms (e.g., with one or more rotary-to-linear mechanisms, spindles, nuts, motors, plates, etc.).

[0039] The one or more pistons may also include a pit or cavity therein that may be used to receive at least a portion of a corresponding rotary-to-linear stage mechanism (e.g., a ball and nut assembly). The piston pit may be a cup or recess formed in an end of the piston. The piston pit may include a bottom wall at an end or bottom of the piston pit and an opposing open end. A gap may exist between the nut of the rotary-to-linear stage mechanism and the corresponding bottom wall. During a brake application operation, the gap may be occupied by moving the rotary-to-linear stage mechanism toward the bottom wall. Once the gap is occupied, further movement of the nut or rotary-to-linear stage mechanism may cause the rotary-to-linear stage mechanism or the rotary-to-linear stage mechanism to press against the bottom wall, and then cause the brake piston and thus the brake pad assembly to move against the brake rotor to generate a clamping force.

[0040] The one or more brake pad assemblies may be used to generate a clamping force. The clamping force may be generated by frictionally engaging the one or more brake pad assemblies with one or more sides of the brake rotor to convert the kinetic energy of the vehicle into heat energy for energy transfer. The one or more brake pad assemblies may include one or more features (i.e., ears, protrusions, etc.) that may engage or be engaged by the brake caliper housing, the support bracket, or both to hold the brake pad assembly within the brake system and in position relative to the brake rotor.

[0041] One or more brake pad assemblies may include one or more components. A brake pad assembly may include a friction material adapted to contact a brake rotor and generate a clamping force. The friction material may be supported or positioned by a shim disposed on a surface of the friction material that is opposite the surface of the friction material that contacts the brake rotor. Similarly, both the shim and the friction material may be supported by a backing plate. The backing plate may be a support portion of the brake pad assembly that receives an input from a piston to move the brake pad assembly. That is, the piston may contact the backing plate such that the backing plate moves the friction material toward the brake rotor. By moving a rotation-to-linear mechanism (e.g., a nut therein) away from contact with the piston within a piston pit, the piston itself may move in an opposite release direction such that the brake pad assembly may move away from the brake rotor, thereby releasing the clamping force. This release direction of the brake pad assembly may be opposite to the direction of movement of the brake pad assembly during a brake application (e.g., clamping) operation.

[0042] The braking system may include an electric motor gear unit (MGU). The MGU may be used to generate a force or torque and transmit the force or torque into a rotation-to-linear mechanism to drive the rotation-to-linear mechanism toward the piston, thereby generating a clamping force. The MGU may also be used to move the rotation-to-linear mechanism away from the piston during a release operation. The MGU may include one or more components that generate a force or torque, transmit a force or torque, or both.

[0043] The MGU may include one or more electric motors. The electric motor may be any electric motor used to generate a force or torque. For example, the electric motor may be a direct current motor, a brushless motor, a series wound motor, a shunt wound motor, a compound wound motor, a split motor, a servo motor, a stepper motor, or a permanent magnet motor. The electric motor may include one or more electrical leads, terminals, connectors, or plugs for connecting the electric motor to a power source, a computer, a processor. Supplying power to the electric motor may cause an output end of the electric motor to rotate about an axis. The output end of the electric motor may be a shaft, a gear, other mechanism, or a combination thereof that extends from the electric motor and is adapted to rotate in an application direction (i.e., generate a clamping force) and an opposite release direction (i.e., release the clamping force).

[0044] The output end of the electric motor can be connected to the gear train of the MGU. The gear train can be used to transfer the force or torque generated from the electric motor to a rotary-to-linear mechanism (e.g., a ball and nut assembly). The gear train can include one or more gears that are meshingly engaged with the output end of the electric motor such that the rotation of the output end of the electric motor causes the rotation of the one or more gears. The one or more gears can be any number of gears that are desired to transfer the force or torque from the output end of the electric motor to the rotary-to-linear mechanism. The one or more gears can vary in size (e.g., diameter, thickness, both), the number of teeth thereon, the size of the teeth, or a combination thereof to effectively and / or efficiently transfer the force or torque from the electric motor to the rotary-to-linear mechanism. The one or more gears can be positioned relative to each other anywhere to transfer the force or torque through the gear train.

[0045] As described above, the braking system can include one or more rotary-to-linear mechanisms, which can also be referred to as rotary-to-linear stage mechanisms. As an example, the rotary-to-linear mechanism can be a ball and nut assembly (BNA). The BNA can be a high-efficiency device such as a ball screw, a roller screw, a ball ramp, etc., or a low-efficiency device such as a lead screw. The BNA can be used to convert the force or torque output from the electric motor into a linear or axial force to move one or more pistons.

[0046] Additionally, it is contemplated that the BNA can provide a reverse driving force such that during a brake release operation, the reverse driving force can at least partially move the BNA in the release direction, thereby at least partially releasing the clamping force between the brake pad assembly and the brake rotor. This reverse driving can be made possible or facilitated by one or more balls, one or more ball springs, one or more bushings, or a combination thereof located within the BNA. This reverse driving can generally also be achieved by the main shaft and the nut of the BNA.

[0047] The main shaft can be rotated by the electric motor or a corresponding drive gear. The main shaft can be rotated in an application direction and a release direction to apply and release the braking system, respectively. The rotation of the main shaft can cause the nut threadedly engaged with the main shaft to axially move along the axis in the application or release direction to move the brake pads towards or away from the brake rotor. The main shaft can be directly driven by the drive gear (e.g., a direct connection or attachment between the two elements). The main shaft can be indirectly driven by the drive gear (e.g., an indirect connection or attachment between the two elements, meaning that one or more gears, shafts, belts, chains, or other intermediate connecting members are disposed between the main shaft and the drive gear).

[0048] The main shaft can include an engagement portion that directly or indirectly receives an input from the drive gear to cause the main shaft to rotate about the axis of rotation. The engagement portion of the main shaft can be the end portion of the main shaft adjacent to the drive gear or the corresponding drive mechanism.

[0049] The nut can move axially along an axis, and the main shaft is configured to rotate about the axis. For example, the nut and the main shaft can be threadedly engaged such that when the main shaft is rotated by a motor or a drive gear, the nut moves axially towards or away from the wall of the piston pit. After contact is formed between the nut and the piston pit wall, further movement of the nut can cause the piston and thus the corresponding end of the brake pad assembly or brake pad to move towards the brake rotor. Rotation of the nut about the axis can also be restricted or prevented, and the nut is configured to move axially along the axis.

[0050] As described above, the rotary-to-linear mechanism (e.g., BNA) can be driven by one or more drive gears. The function of the drive gear is to transfer force or torque from a motor or a gear train to the corresponding main shaft of the BNA. The drive gear can frictionally engage the corresponding main shaft. The drive gear can engage the corresponding main shaft via ridges and corresponding notches defined on the receiving portion of the main shaft and / or on the drive gear.

[0051] The drive gear can be connected to the gear train or can be part of the gear train. In either case, the drive gear can be a gear that receives force or torque from the gear train or directly from the motor to transfer the force or torque directly or indirectly to the BNA. To transfer force or torque, the drive gear can include an output end.

[0052] The output end can be a shaft or a gear that extends from the drive gear towards the BNA. The output end can directly engage the main shaft (e.g., its engaging portion) or can be indirectly connected to the main shaft to rotate the main shaft. The output end of the drive gear can rotate about the axis of rotation. Such an axis can be parallel or coaxial with the axis of rotation of the main shaft, the axis of rotation of the motor output end, or a combination thereof. The output end can be a gear that is connected to one or more additional gears that contact the main shaft to rotate the main shaft.

[0053] As an example, the output end of the drive gear can be a sun gear that is connected to one or more planet gears of a planetary gear system. When the sun gear rotates due to the rotation of the drive gear, one or more planet gears can also rotate, thereby rotating a member or component connected to the main shaft. As a result, the main shaft can be rotated in turn.

[0054] The drive gear can also be connected to a plate. The plate can be used to assist in releasing one or more brake pad assemblies during a release operation. The plate can be used to rotate the drive gear in the brake application direction, the brake release direction, or both. The plate can be adapted to rotate simultaneously with the drive gear. The plate is adapted to rotate independently of the drive gear and vice versa. Thus, the plate and the drive gear can be rotatably engaged with each other to facilitate such rotation.

[0055] To facilitate such rotation of the plate and the drive gear, the plate may include a shaft. The shaft may project or extend through the plate to connect to the drive means. The shaft may project or extend through the plate to connect the motor gear unit (MGU) housing to the plate. The shaft may extend through the MGU housing to maintain the axial position of the MGU housing along the axis of rotation of the plate. To axially fix the MGU housing along the shaft, one or more clips or fasteners may be secured to the shaft and / or the MGU housing.

[0056] The shaft may rotatably connect the plate and the drive gear such that the plate and the drive gear are coaxial. Thus, the plate and the drive gear may share the axis of rotation. The axis of rotation of the plate and the drive gear may be parallel or coaxial with the axis of rotation of the main shaft of the BNA.

[0057] The plate may rotate the drive gear, the drive gear may rotate the plate, or both. The plate may engage the drive gear during rotation of the plate, or the drive gear may engage the plate during rotation of the drive gear.

[0058] The drive gear may include one or more pins that engage the plate during rotation. The one or more pins may project or extend from the surface of the drive gear towards the plate. The one or more pins may be connected to one or more fins of the plate such that when the one or more pins contact the one or more fins during rotation of the drive gear, the plate may also rotate in the same direction as the drive gear.

[0059] The one or more pins may be a plurality of pins. The pins of the drive gear may be located anywhere along the surface of the drive gear. The pins may be located around or near the peripheral edge of the drive gear. The pins may be located towards the axis of rotation of the drive gear in the central portion or near the central hole of the drive gear. The pins may be formed integrally with the drive gear or may be connected to the drive gear. The pins may be formed in any shape (e.g., any length measured from the distal end of the drive gear to the surface, any diameter, any curvature, etc.). The pins may be shaped to ensure contact between the pins and one or more fins of the plate during rotation of the drive gear, rotation of the plate, or both.

[0060] One or more fins of the plate may project or extend from the surface of the plate. The surface of the plate including the one or more fins may face the surface of the drive gear including the one or more pins. As described above, the one or more fins may be contacted by the one or more pins during rotation of the drive gear such that when the drive gear rotates, the plate also rotates in the same direction. Such rotation may occur during a brake application operation during which the drive gear is driven by a motor to rotate a linear mechanism.

[0061] Similarly, the plate can initiate rotation of the drive gear. That is, the plate can rotate such that one or more fins contact one or more pins of the drive gear. Accordingly, the drive gear can rotate in the same direction as the rotation of the plate. This rotation can occur during a brake release operation during which the drive gear is moved in a release direction by an electric motor. Advantageously, however, the plate can also provide means for rotating the drive gear in a release direction independently of the electric motor. In other words, if the electric motor fails and becomes inoperable or otherwise unable to drive the drive gear in a brake application direction, a brake release direction, or both, the plate can generate sufficient force or torque to rotate the drive gear in a release direction. The force or torque generated by the plate can be sufficient to cause a rotation-to-linear mechanism (e.g., a BNA) to rotate in a release direction to disengage one or more brake pad assemblies from a brake rotor.

[0062] One or more fins of the plate can facilitate rotation of the drive gear in a release direction. Additionally, one or more fins can allow rotation of the drive gear to be free or independent of rotation of the plate. To this end, one or more fins can be compressible, flexible, elastic, movable, or a combination thereof. Such compression, flexibility, elasticity, movability, or a combination thereof can exist when a force applied to one or more fins reaches or exceeds a specified threshold.

[0063] For example, during a brake application operation, pins of the drive gear can contact one or more fins of the plate during rotation of the drive gear, thereby also causing the plate to rotate in the same direction as the drive gear. Once the drive gear has rotated a desired amount or reached a stop point in a brake application or clamping direction, further rotation of the plate in a brake application or clamping direction can be prevented. As a result, the pins and the drive gear can remain driven by the electric motor such that the force applied by the pins of the drive gear on the now stationary one or more fins of the plate can increase. Once such force increases beyond a specified threshold force, one or more fins can deflect to allow the drive gear to continue rotating in a brake application or clamping direction.

[0064] To accommodate the above-described capabilities of the fins, the fins can have any desired shape, length, height, width, etc. The fins can include one or more linear segments, one or more arcuate segments, one or more curves, one or more notches, one or more grooves, one or more points, one or more tips, one or more bases, or a combination thereof. The fins can have one or more arms, one or more fingers, or both. The fins can be adjusted or shaped to produce a desired force threshold for deflection based on a given brake system application.

[0065] The fins can be strengthened. The strengthening can be carried out locally only along a part of the fin, or can be carried out along the entire fin. Only a part of the fin can be strengthened, or the entire fin can be strengthened. In some applications, the fins can also be unstrengthened. However, when the strengthening is incorporated into the fin, the strengthening can be a locally increased thickness of the fin, a strengthening feature of the fin (e.g., gussets, ribs, arms, etc.), an auxiliary material connected or disposed to the fin, or a combination thereof.

[0066] As described above, the plate can rotate the drive gear through one or more fins, particularly to rotate the drive gear in the brake release direction. To this end, the plate can generate or otherwise store a force or torque that can be applied to the drive gear to rotate the drive gear. Such a force or torque can be generated and / or stored in a biasing member of the plate.

[0067] The biasing member can be used to generate a force or torque. The biasing member can be used to rotate the plate using the generated force or torque, thereby allowing the plate to contact the drive gear and rotate the drive gear. The force or torque can be stored in the biasing member. The force or torque can be generated by moving the biasing member or applying a load to the biasing member. The movement of the biasing member or the load applied to the biasing member can be carried out during the brake application operation, such that the force or torque generated and stored in the biasing member can be released during the brake release operation.

[0068] For example, the biasing member can be an elastic member. The elastic member can be stretched during the rotation of the plate during the brake application operation. The stretching can generate a force or torque stored within the biasing member. When the brake system starts the brake release operation, the plate can start to rotate in the release direction, thereby releasing the force or torque stored in the elastic member. Therefore, the released force or torque can also help the drive gear to rotate in the release direction.

[0069] Although the biasing member as described herein can be connected to or otherwise associated with the plate of the motor gear unit, it is contemplated that the biasing member can be located anywhere within the brake system. That is, the biasing member can be positioned or adapted to engage any gear within the gear train, can be positioned or adapted to engage one or more drive gears, or both. Similarly, the biasing member can be positioned adjacent to the gear train, one or more drive gears, or both, such that the biasing member can be associated with the motor gear unit without directly displacing any gear within the motor gear unit. That is, the biasing member can be a separate mechanism associated with the motor gear unit.

[0070] The biasing member can be a spring. The spring can be a helical spring, a torsion spring, a cylindrical helical spring, a disc spring, a leaf spring, a volute spring, a tension spring, a compression spring, or a combination thereof.

[0071] The biasing member can be fixed to the plate. The biasing member can include a coiled or wound portion that is at least partially wound around an axis of the plate. The biasing member can be mounted or otherwise clamped to the plate. The biasing member can be disposed along a lower surface of the plate that is opposite the surface of the plate having one or more fins.

[0072] The biasing member can include one or more arms. The arms can be used to engage one or more features of the plate, one or more features of the MGU housing, or both. The arms can be fixed or can be freely movable. The arms can extend from a central portion of the biasing member to contact one or more features of the plate, one or more features of the MGU housing, or both. The one or more features can be clamps, clips, protrusions, ridges, engagement features, stops, etc. of the plate and / or the MGU housing that can prevent movement of the one or more arms completely or in a desired direction.

[0073] For example, the biasing member can include a first arm and a second arm that extend away from a central coiled portion of the biasing member. The first arm can engage a protrusion or ridge that prevents complete movement of the first arm. In contrast, the second arm can be located between opposing ridges or protrusions positioned along the plate or the MGU housing such that the second arm can move freely between the opposing ridges or protrusions. When a braking application operation, a braking release operation, or both are completed, the opposing ridges or protrusions associated with the second arm can define a stopping point of the second arm during movement of the second arm.

[0074] The arms of the biasing member can be linear, can include one or more arcuate segments, can include one or more fingers, can include one or more protrusions, or a combination thereof to engage the plate, the MGU housing, or both.

[0075] It should be noted that the MGU housing disclosed herein can be adapted to receive or accommodate all or a portion of an electric motor gear unit (e.g., an electric motor, a gear train, a drive gear, a plate, etc.). The MGU housing can include one or more portions that are interconnected to form the housing. The MGU housing can include one or more openings, one or more doors, one or more panels, one or more covers, or a combination thereof. The MGU housing can include one or more recesses or channels that receive some or all of the components of the MGU. The MGU housing can include one or more features connected to the MGU. The one or more features can be one or more protrusions or ridges, one or more clips, one or more holes, one or more protrusions, one or more ribs, etc.

[0076] It should be noted that any gear disclosed herein (e.g., the motor output end, the drive gear, the drive gear output end, the gears within the gear train, the planetary gear system, etc.) can be replaced by two or more gears. Any two or more gears disclosed herein can be replaced by a single gear. One or more intermediate gears can be disposed between any two or more gears disclosed herein that are in direct meshing engagement with each other. Any intermediate gear between two or more other gears disclosed herein can be eliminated.

[0077] Any gear disclosed herein can be a spur gear, a helical gear, a bevel gear, a worm gear. In other words, for example, although a spur gear may be referred to, the spur gear can be replaced by any gear (such as a helical gear).

[0078] Although the gears disclosed herein are described as having teeth that mesh or engage with other toothed gears to transfer torque between the gears, it should be understood that other means can be used to transfer torque, such as using one or more belts, chains, intermediate gears, shafts, rack and pinion, axles, etc. In addition, in certain applications, the teeth on one or more gears can be eliminated, and the gears can be engaged with each other by a press or friction fit to transfer torque. Further, any gear disclosed herein can be replaced by a shaft, a belt, a chain, or other torque transfer means. In addition, any gear disclosed herein and its orientation can be rearranged and still be within the scope of the present disclosure.

[0079] The gears and / or plates disclosed herein can be made of any material, such as metal, plastic, 3D printing, etc.

[0080] One or more bearings and / or bushings can be disposed at any interface where one or more gears and / or plates are described as rotating about a shaft or axis.

[0081] The braking systems and / or clamping forces disclosed herein can be used for any vehicle (i.e., passenger car or van, truck, multi - purpose vehicle or off - road vehicle). The braking systems and / or clamping forces disclosed herein can be used for service brake applications (i.e., slowing down, stopping, or preventing the movement of the wheels or vehicle). The braking systems and / or clamping forces disclosed herein can be used for parking brake applications (i.e., preventing the movement of the wheels or vehicle). The braking systems and / or clamping forces disclosed herein can be used for parking brake applications while a hydraulic or other braking system is used for service brake operation.

[0082] Now turning to the drawings, Figure 1A perspective view of a braking system 20 in accordance with the present teachings is shown. The braking system 20 may include a brake caliper housing 22 that at least partially houses one or more brake pad assemblies 24. As shown, the brake caliper housing 22 may include a first brake pad assembly 24A and a second brake pad assembly 24B. When a rotor is at least partially housed within the brake caliper housing 22, the first brake pad assembly 24A and the second brake pad assembly 24B may be located on opposite sides of the rotor (not shown). Accordingly, the brake pad assemblies 24 may be configured to contact the rotor during a braking application operation.

[0083] To facilitate the braking application operation, the braking system 20 may include a motor gear unit (MGU) 40 that is housed within an MGU housing 42. As described in further detail below, the MGU 40 may include a motor coupled to one or more gears such that a drive gear may drive a ball and nut assembly (BNA) housed within the brake caliper housing 22 into contact with a piston (see, for example Figure 3 ). Accordingly, the piston may be driven into contact with the first brake pad assembly 24A such that the first brake pad assembly 24A moves in a clamping direction (C) to contact the rotor. Similarly, as the first brake pad assembly 24A moves in the clamping direction (C), the second brake pad assembly 24B may move in an opposite direction to contact the other side of the rotor. As a result, the brake pad assemblies 24 may clamp the rotor and generate a braking force. Once the braking application operation is complete, the first brake pad assembly may be released and move in a release direction (R) to not contact the rotor. Similarly, the second brake pad assembly 24B may move in a direction opposite to the release direction (R) to also not contact the rotor.

[0084] Figure 2 is shown Figure 1 A perspective view of the braking system 20 shown. For simplicity and clarity, the motor gear unit (MGU) housing has been removed. As described above, the braking system 20 may include a brake caliper housing 22 that houses one or more brake pad assemblies that are configured to clamp a rotor of a vehicle.

[0085] Based on the torque generated by the electric motor 50 of the motor gear unit (MGU) 40, the brake pad assembly can move in the clamping direction (i.e., towards the rotor), in the release direction (i.e., away from the rotor), or in both directions. As shown, the electric motor 50 can include an electric motor output end 52 that outputs the torque generated by the electric motor 50. The electric motor output end 52 can be a gear or other mechanism connected to the electric motor 50. To output torque, the electric motor output end 52 can be adapted to rotate about an axis (A1). The axis (A1) can be the rotational axis of the electric motor 50 or a different axis. For example, the axis (A1) can be parallel to the rotational axis of the electric motor 50 or deviate from the rotational axis of the electric motor 50 in some way. However, it is contemplated that the electric motor output end 52 can be arranged around the rotational axis of the electric motor 50 (i.e., the axis (A1) is the rotational axis of the electric motor) to transfer the torque generated by the electric motor 50 efficiently and effectively.

[0086] The electric motor output end 52 can be connected to the gear train 60 of the MGU (40). The gear train 60 can include one or more gears 62 that are interconnected or otherwise connected to each other to transfer the torque from the electric motor output end 52 through the gear train 60. That is, the electric motor output end 52 can engage at least one gear 62 of the gear train 60 to transfer the torque generated by the electric motor 50 to the gear 62. As a result, the gear 62 connected to the electric motor output end 52 can then transfer the generated torque to one or more additional gears within the gear train 60, allowing the torque generated by the electric motor 50 to travel along the entire gear train 60. It should be noted that the gear train 60 can include any number and type of gears 62. Those skilled in the art will understand that various gear train 60 configurations may be possible or desirable based on the specific brake system 20 or vehicle application.

[0087] The gear train 60 can receive torque from the electric motor output end 52 and transfer such torque to the drive gear 64. That is, the torque output from the electric motor 50 through the electric motor output end 52 can travel through the gear train 60 until the torque is received by the drive gear 64. Thus, the drive gear 64 can transfer the torque to the ball and nut assembly (BNA; not shown) by rotating about the rotational axis (A2) of the drive gear 64, allowing the BNA to move the piston of the brake system 20 into contact with one or more brake pad assemblies (see Figure 1 and Figure 3 ). As Figure 2As shown, the axis of rotation (A2) of the drive gear 64 can be offset from the axis of rotation (A1) of the electric motor 50 and / or the electric motor output 52. The axes (A1, A2) can be parallel to each other, can converge towards each other, or can diverge from each other. However, as shown, it is contemplated that the axis of rotation (A2) of the drive gear 64 can be parallel to the axis of rotation (A1) of the electric motor 50 to efficiently transfer the torque generated by the electric motor 50.

[0088] The drive gear 64 can also be connected to a plate 74 positioned adjacent to the drive gear 64. The plate 74 can be located on the opposite side of the drive gear 64 relative to the BNA of the brake system 20. The plate 74 can also be configured to rotate about the axis of rotation (A2) of the drive gear 64. Additionally, the plate 74 can include a shaft 76 extending through the plate 74 and the drive gear 64. The shaft 76 can be configured to hold the lateral position of the biasing member 80 while also facilitating rotational movement of the plate 74 and the drive gear 64 relative to each other. For example, the biasing member 80 can be at least partially wound around the shaft 76. The biasing member 80 can also include a first arm 82A abutting the protrusion 84 of the plate 74 and a second arm 82B configured to contact one or more protrusions (see Figure 12 ) located on the housing of the MGU.

[0089] Figure 3 A cross-sectional view of the brake system 20 according to the present teachings is shown. The brake system 20 can include a brake caliper housing 22 that houses one or more brake pad assemblies 24. For simplicity, although the brake caliper housing 22 can include opposing brake pad assemblies 24, only the first brake pad assembly 24A is shown. The brake pad assembly 24A can include a friction material 28 fixed to a shim 30 and / or a backing plate 26. As a result, a piston 36 of the brake system 20 located within the piston housing 34 of the brake caliper housing 22 can contact the backing plate 26 and move the friction material 28 into contact with the vehicle's rotor.

[0090] To drive the piston 36, the brake system 20 may include a ball and nut assembly (BNA) 54. The BNA 54 may include a nut 58 threadedly engaged with a main shaft 56 such that rotation of the main shaft 56 may cause linear movement of the nut 58 until the contact surface 58A of the nut 58 contacts the piston 36 and moves the piston 36 toward the pressure plate 26. Rotation of the main shaft 56 may be achieved by a drive gear 64 of the brake system 20. In particular, the drive gear 64 may include an output end 66 connected to an engagement portion 56A of the main shaft 56. The output end 66 of the drive gear 64 may be connected to a planetary gear system 72 that converts rotation of the drive gear 64 into rotation of the main shaft 56. Thus, rotation of the drive gear 64 may drive the main shaft 56 to rotate about a rotation axis (A2). As shown, it should be noted that the rotation axis (A2) of the main shaft 56 may also be the rotation axis (A2) of the drive gear 64.

[0091] The driving of the drive gear 64 may be facilitated by a motor gear unit (MGU) of the brake system 20 located within the MGU housing 42 and / or the cover 44. More specifically, the motor of the MGU may generate torque that is transferred through a gear train into the drive gear 64, which subsequently ultimately drives the BNA 54 to contact the piston 58 and move the first brake pad assembly 24A (see Figure 2 ). That is, during a brake application operation, the movement of one or more brake pad assemblies may be generated substantially or entirely by the motor.

[0092] Conversely, during a release operation in which the brake pad assembly moves away from the vehicle's rotor toward the starting position, the motor may work in conjunction with the BNA 54. In particular, the BNA 54 may include one or more ball springs 100 that allow the BNA 54 to freely generate a reverse driving force (i.e., torque) through the main shaft 56 to assist in releasing the brake pad assembly. For example, the ball springs 100 (or individual balls in some assemblies) may be located between the nut 58 and the main shaft 56 such that when the nut 58 is pressed against the piston 58 and the brake system 20 is released to begin retraction of the piston 58, the ball springs 100 may facilitate free rotation of the main shaft 56 in the release direction (i.e., opposite the rotational direction for clamping). Due to the reverse driving generated by the BNA 54, the motor of the brake system 20 may need to generate less torque in the release direction.

[0093] However, in some cases of motor failure (e.g., power failure and / or mechanical failure of the motor), the reverse drive generated only from the BNA 54 may not be sufficient to release the brake pad assembly enough to disengage from the vehicle's rotor. That is, without the motor generating torque in the release direction, the reverse drive may not be sufficient to release the brake pad assembly. To accommodate these situations, the brake system 20 can advantageously include a plate 74 connected to the drive gear 64.

[0094] The plate 74 can include a shaft 76 extending through the plate 74 and connected to the drive gear 64 to allow rotational movement of the plate 74 and the drive gear 64 relative to each other. The drive gear 64 can include a plurality of pins 68 projecting from the surface of the drive gear 64 toward the plate 74. During a brake application operation, the pins 68 can contact one or more fins 78 projecting from the surface of the plate 74 toward the drive gear 64 such that rotation of the drive gear 64 can also cause the plate 74 to rotate about the axis of rotation (A2). Additionally, although discussed further in detail below, the plate 74 rotated by the drive gear 64 can cause a biasing member 80 wound around the shaft 76 of the plate and secured with a clip 102 to be wound (e.g., twisted).

[0095] If the motor of the brake system 20 fails, the reverse drive of the BNA 54 can begin to rotate in the release direction to disengage the brake pad assembly from the vehicle's rotor. Advantageously, during such reverse drive, the biasing member 80 can also unwind to release the loading torque caused by the brake application operation in the biasing member 80. By unwinding the biasing member 80, one or more fins 78 of the plate 74 can contact the pins 68 of the drive gear 64, thereby driving the drive gear 64 to rotate in the same release direction as the plate 74. Thus, the biasing member 80 can work in conjunction with the reverse drive of the BNA 54 to increase the torque during the release operation to sufficiently retract the brake pad assembly away from the rotor.

[0096] Figure 4 A perspective view of the drive gear 64 of the brake system according to the present teachings is shown. As described above, the drive gear 64 can be directly or indirectly connected to the motor output 52. The motor output 52 can be configured to directly or indirectly transfer the torque generated by the motor to the drive gear 64 such that the drive gear can transfer the generated torque through the output 66 into the BNA of the brake system, thereby moving the piston toward the brake pad assembly during a brake application operation.

[0097] In some cases, the motor output end 52 can be directly connected to the drive gear 64. For example, the motor output end 52 can be a gear having a plurality of teeth that mesh with the plurality of teeth of the drive gear 64. Thus, the rotation of the motor output end 52 caused by the motor can be directly converted into the rotation of the drive gear and the output end 66 therein.

[0098] However, as Figure 4 shown, the motor output end 52 can indirectly drive the drive gear 64 through the gear train 60. The gear train 60 can include one or more gears 62 that receive torque through the motor output end 52. The torque can then travel through the gear train 60 until it reaches the drive gear 64. Additionally, the drive gear 64, one or more gears 62 within the gear train 60, the motor output end 52, or a combination thereof can be at least partially housed within one or more portions of the motor gear unit (MGU) housing 42. For example, although only a portion of the MGU housing 42 is shown in Figure 4 , it can be seen that at least the drive gear 64 can be at least partially housed within the recess 48 of the MGU housing 42. Similarly, a plate (not shown) located between the drive gear 64 and the MGU housing 42 can also be located within the recess 48.

[0099] Figure 5 A perspective view of the motor gear unit (MGU) housing 42 is shown, with the cover removed. The view as shown shows the opposite side of the MGU housing 42 from that shown in Figure 4 .

[0100] As described above, a plate can be located between the drive gear and the MGU housing 42. Thus, the shaft 76 of the plate can extend through the MGU housing 42 such that the clip 102 can secure the MGU housing 42 to the shaft 76 of the plate, thereby allowing the plate and / or the drive gear to rotate while maintaining the lateral position of the plate, the drive gear, the MGU housing 42, or a combination thereof.

[0101] Figure 6 and Figure 7 A perspective view of the drive gear 64 connected to the plate 74 of the braking system is shown. As described above, the drive gear 64 can include an output end 66 that is adapted to be connected to the BNA of the braking system to drive the BNA during a braking application operation, a release operation, or both. The output end 66 can be a gear and / or a shaft extending from the drive gear 64 that can directly or indirectly transfer the generated torque through the drive gear 64 to the BNA.

[0102] The drive gear 64 and the plate 74 can be engaged to rotate about an axis 76 that extends through the plate 74. That is, the plate 74 and the drive gear 64 can rotate synchronously in the same direction, asynchronously in opposite directions, or both. For example, during a brake application operation, the drive gear 64 can be driven via an electric motor of the brake system to rotate in a first direction (e.g., clockwise). When the drive gear 64 rotates, a pin 68 that projects from the surface of the drive gear 64 toward the plate 74 can contact one or more fins 78 along the surface of the plate 74 that faces the drive gear 64. As a result, the pin 68 can in turn cause the plate 74 to rotate with the drive gear 64 via the one or more fins 78.

[0103] As shown, the plate 74 can include a biasing member 80, such as a spring, that at least partially wraps around the axis 76 of the plate 74. The biasing member 80 can include a first arm 82A having an opposing second arm 82B. The first arm 82A can abut or otherwise be fixed to a protrusion 84 that projects from the surface of the plate 74. Similarly, the second arm 82B can be located at or fixed to an additional protrusion that is located on an auxiliary component, such as the surface of an electric motor gear unit (MGU) housing (see Figure 12 ).

[0104] When the drive gear 64 engages the plate 74 such that the plate 74 rotates with the drive gear 64 (e.g., during a brake application operation), the biasing member 80 can be wound (e.g., twisted). That is, since the first arm 82A is fixed by contacting the protrusion 84 of the plate 74, the second arm 82B of the biasing member 80 can freely rotate along the axis of rotation of the plate 74, the drive gear 64, or both until the second arm 82B reaches a stop point (see Figure 12 ). Once the second arm 82B reaches the stop point, the biasing member 80 can be fully wound.

[0105] One or more fins 78 of the plate 74 can be elastic, compressible, or otherwise movable such that when the drive gear 64 rotates with sufficient torque to overcome a specified threshold, the pin 68 can contact the one or more fins 78 and deflect the one or more fins 78 to allow the drive gear 64 to continue rotating. This threshold of torque generated by the drive gear 64 to deflect the one or more fins 78 can be achieved during a brake application operation after the second arm 82B of the biasing member 80 has reached its stop point. That is, when the second 82B prevents further winding of the biasing member 80, the pin 68 of the drive gear 64 can deflect the one or more fins 78 and allow the drive gear 64 to continue rotating to drive the BNA of the brake system.

[0106] During a release operation, the drive gear 64 can begin to rotate in a direction opposite to the direction of rotation during a brake application operation. During normal operation of the braking system, movement of the drive gear 64 in the release direction can be driven by an electric motor of the braking system through a planetary gear (see Figure 2 ). Additionally, the BNA can be adapted to allow backdriving, whereby the BNA itself begins to move in the release direction, thereby also driving the drive gear 64 in the release direction.

[0107] However, during a motor failure, the motor may not be able to move the drive gear 64 in the release direction and thus may not be able to move the BNA in the release direction to disengage the piston from one or more brake pad assemblies of the braking system (see Figure 3 ). Thus, one or more brake pad assemblies must typically rely only on the backdriving generated by the BNA. Unfortunately, this backdriving may typically not be sufficient to release the brake pad assemblies from contact with the vehicle's rotor. Thus, due to the contact, a drag condition may exist, which can deteriorate the rotor, one or more brake pad assemblies, or both during vehicle operation.

[0108] Advantageously, the present design facilitates the use of a biasing member 80 to increase the backdriving force and accommodate motor failure. More specifically, as described above, the biasing member 80 can be wound to store energy during a brake application operation. During a release operation, the energy stored in the biasing member 80 can be freely released, thereby unwinding the biasing member 80 to return the biasing member 80 to its original position before winding. During this unwinding, the second arm 82B of the biasing member can be released from the stop point reached during brake application, causing the plate 74 to rotate in the release direction. Thus, one or more fins 78 of the plate 74 can contact the pins 68 of the drive gear 64 and cause the drive gear 64 to also rotate in the release direction, thereby driving the BNA to retract from the engaged piston. The biasing member 80 can continue to unwind and release its stored energy until the second arm 82B reaches its original position. The original position can be a second protrusion on the MGU housing or other position that prevents further movement of the second arm 82B in the release direction. Thus, based on the above, even during a motor failure, the biasing member 80 working in conjunction with the backdriving of the BNA is sufficient to release one or more brake pad assemblies from contact with the rotor. However, it should also be noted that the biasing member 80 can also work together with the backdriving of the BNA and the release torque generated by the motor during normal operating conditions to release one or more brake pad assemblies. Thus, even during normal operation, the biasing member 80 can advantageously improve the efficiency of the release operation.

[0109] Figure 8A perspective view of the drive gear 64 connected to the plate 74 of the braking system is shown. As described above, the drive gear 64 may include a plurality of pins 68 protruding from the surface of the drive gear 64 towards the plate 74. The pins 68 may be adapted to contact one or more fins 78 during rotation such that rotation of the drive gear 64 may cause the plate 74 to rotate. Additionally, similar to the plate 74 shown in Figure 6 and Figure 7 , the plate 74 may include a biasing member 80 that is at least partially wound around the axis 76 of the plate 74 and axially fixed in place by a clip 102.

[0110] However, although the plate 74 shown in Figure 6 and Figure 7 includes a torsion spring as the biasing member 80, the present plate 74 includes a helical spring wound around the axis 76 of the plate 74. The biasing member 80 may include an arm 82 that extends to connect to a protrusion 84 on the plate 74. Although not shown, the arm 82 may also be routed along the surface of the plate 74 against or otherwise by one or more additional protrusions 84. For example, the arm 82 may extend around a plurality of protrusions until it reaches the protrusion 84 for connection.

[0111] During a braking application operation, the drive gear 64 may rotate such that the pins 68 contact one or more fins 78 of the plate 74, causing the plate 74 to rotate with the drive gear 64. When the plate 74 rotates, the biasing member 80 may also rotate to further wind the coiled portion of the biasing member 80 located around the axis of the plate 74. This winding may continue until the force to further wind the biasing member 80 exceeds a threshold to deflect one or more fins 78, at which point the pins 68 may deflect one or more fins 78 to allow the drive gear 64 to continue rotating while the biasing member 80 remains wound.

[0112] Similarly, it is also conceivable that the biasing member 80 may be elastic such that rotation of the plate 74 may stretch the arm 82 and increase the tension in the arm 82. However, such elasticity is not necessary for the operation of the biasing member 80 as described above.

[0113] During a release operation, the plate 74 may rotate freely in a direction opposite to that during the braking application operation. As a result, the biasing member 80 may also freely unwind to release the stored energy obtained during the braking application operation. Thus, the biasing member 80 may assist the rotation of the plate 74. As the plate 74 rotates, one or more fins 78 on the plate 74 may contact the pins 68 of the drive gear 64, causing the drive gear 64 to also rotate with the plate 74.

[0114] Figure 9 and Figure 10A perspective view of the drive gear 64 connected to the plate 74 of the braking system is shown. The drive gear 64 in each figure is made transparent to better show the connection between the drive gear 64 and the plate 74.

[0115] As shown, the drive gear 64 may include a plurality of pins 68 located around the surface of the plate 74. The pins 68 may be positioned radially away from the axis of the drive gear 64 such that the distance of each pin 68 from the axis of the drive gear 64 is consistent. However, the pins 68 may also be positioned in any desired manner, whether uniformly, patterned, positioned in a varying manner, or a combination thereof. For example, the pins 68 may be spaced evenly around the entire circumference of the drive gear 64. However, the pins 68 may also include one or more different gaps between the pins 68 such that the pins 68 are not equally spaced around the circumference of the drive gear 64. Additionally, the pins 68 may be positioned anywhere along the surface of the drive gear 64.

[0116] During rotation of the drive gear 64, the pins 68 may contact a plurality of fins 78 of the plate 74. The fins 78 may extend radially from the axis of the plate 74. Similarly, the fins 78 may be spaced evenly, although such spacing may not be required.

[0117] As Figure 9 shown, the fins 78 may include a curved or arcuate segment along the fins 78. The fins 78 may also include a reinforcing portion 78A to locally reinforce a portion of the fins 78 and improve the structural integrity of the fins 78. However, depending on the given application, such local reinforcement may not be present.

[0118] Conversely, as Figure 10 shown, the fins 78 may also be substantially linear segments or protrusions along the plate 74 without a curved or arcuate segment. Thus, it can be seen from this teaching that various shapes can be achieved for the fins 78. Therefore, the fins 78 can be rotated to adjust the threshold at which the fins 78 are deflected by the pins 68 during operation of the braking system. Thus, the fins 78 can advantageously accommodate various types of braking systems having varying forces applied therein.

[0119] Figure 11 A perspective view of the drive gear 64 is shown. The drive gear 64 may include a plurality of pins 68 protruding from the surface to engage the fins of the plate (see, for example Figures 6 to 10 ). Additionally, the drive gear 64 may include a hole 70 positioned around the axis of the drive gear 64. The hole 70 may be circular or may include one or more anti-rotation features therein. For example, as shown, the hole 70 may include one or more flat segments that engage the output end of the drive gear 64 such that rotation of the drive gear 64 can thereby rotate the output end (see Figure 3). This output end can be a gear or a shaft. Similarly, the hole 70 of the drive gear 64 can also at least partially receive the shaft of the plate so that the drive gear 64 and the shaft can rotate freely together or relative to each other around the same axis of rotation.

[0120] Figure 12 A perspective view of a plate 74 of a brake system fixed to a motor gear unit (MGU) housing 42 is shown. The housing 42 has been made transparent to further illustrate the engagement with the plate 74.

[0121] As discussed in detail above, the plate 74 may include a biasing member 80 positioned about the shaft 76 of the plate 74. The biasing member may be positioned between a surface of the housing 42 and a surface of the plate 74, whereby the shaft 76 may extend through the housing 42 such that the housing 42 is secured to the shaft 76 by the clip 102.

[0122] The biasing member 80 may include a first arm 82A and an opposing second arm 82B. The first arm 82A may be fixed to a projection 84 located on the plate, or fixed in place in any desired manner. In contrast, the second arm 82B may be free to rotate between a first projection 86A of the housing 42 and a second projection 86B of the housing 42. For example, the second arm 82B may be in a resting position against the first projection 86A of the housing 42 prior to a brake application operation. During a brake application operation, the biasing member 80 may be wound to load a force to the biasing member 80. Since the first arm 82A is fixed to the projection 84 of the plate 74, the biasing member 80 may continue to be wound until the second arm 82B moves away from the first projection 86A of the housing and reaches the second projection 86B of the housing, at which point further winding is prevented.

[0123] In contrast, during a release operation, the biasing member 80 is free to expand and rotate the plate 74 in the release direction until the second arm 82B moves back to its original position in contact with the first protrusion 86A of the housing 42, thereby preventing the second arm 82B from further rotating in the release direction.

[0124] The explanations and illustrations given herein are intended to familiarize other persons skilled in the art with the present invention, its principles and its practical applications. The above description is intended to be illustrative and not restrictive. Those skilled in the art may adjust and apply the present invention in a variety of forms that best suit the requirements of a particular application.

[0125] Accordingly, the specific embodiments of the invention as set forth are not intended to be an exhaustive or limiting teaching. Thus, the scope of the teaching should not be determined with reference to this specification, but rather should be determined with reference to the appended claims and the full scope of the equivalents given by those claims. The omission of any aspect of the subject matter disclosed herein in the appended claims is not a waiver of such subject matter, nor should it be considered that the inventors do not consider such subject matter to be part of the disclosed inventive subject matter.

[0126] A plurality of elements or steps may be provided by a single integrated element or step. Alternatively, a single element or step may be divided into separate multiple elements or steps.

[0127] The disclosure of "a" or "an" element or step does not intend to exclude additional elements or steps.

[0128] Although the terms "first", "second", "third", etc. may be used herein to describe various elements, components, regions, layers, and / or sections, these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms may be used to distinguish one element, component, region, layer, or section from another. Unless the context clearly indicates otherwise, terms such as "first", "second", and other numerical terms do not imply a sequence or order when used herein. Thus, the first element, component, region, layer, or section below may be referred to as the second element, component, region, layer, or section without departing from the teaching.

[0129] For ease of description, spatially relative terms such as "inner", "outer", "beneath", "below", "lower", "above", "upper", etc. may be used herein to describe the relationship of one element or feature to another element or feature as shown in the figures. In addition to the orientation depicted in the figures, spatially relative terms are intended to encompass different orientations of the device during use or operation. For example, if the device in the figures is flipped, an element described as "above" or "beneath" another element or feature will be oriented "below" or "above" the other element or feature. Thus, the exemplary term "below" can encompass both "above" and "below" orientations. The device may be otherwise oriented (rotated 90 degrees or in other orientations), and the spatially relative descriptors used herein are to be interpreted accordingly.

[0130] The disclosures of all articles and references (including patent applications and publications) are incorporated by reference in their entirety for all purposes. Other combinations are possible, as will be gathered from the appended claims, which are also incorporated by reference into this written description.

[0131] Unless otherwise specified, the teachings of the terms "about" or "approximate" in combination with a numerical quantity cover the teaching of that quantity and an approximation of that quantity. For example, the teaching of "about 100" covers the teaching within the range of 100 + / - 15.

[0132] Component List

[0133] 20 Brake System

[0134] 22 Brake Caliper Housing

[0135] 24 Brake Pad Assembly

[0136] 24A First Brake Pad Assembly

[0137] 24B Second Brake Pad Assembly

[0138] 26 Pressure Plate

[0139] 28 Friction Material

[0140] 30 Spacer

[0141] 34 Piston Housing

[0142] 36 Piston

[0143] 40 Motor Gear Unit (MGU)

[0144] 42 Motor Gear Unit (MGU) Housing

[0145] 44 Cover

[0146] 46 Housing Fastener

[0147] 48 Groove

[0148] 50 Motor

[0149] 52 Motor Output Shaft

[0150] 54 Spindle and Nut Assembly

[0151] 56 Spindle

[0152] 56A Engagement Portion of the Spindle

[0153] 58 Nut

[0154] 58A Contact Surface of the Nut

[0155] 60 Gear Train

[0156] 62 Gear

[0157] 64 Driving Gear

[0158] 66 Output Shaft of the Driving Gear

[0159] Pin of the drive gear

[0160] Hole of the drive gear

[0161] Planetary gear system

[0162] Plate

[0163] Shaft of the plate

[0164] Fin of the plate

[0165] Reinforcement of the fin

[0166] Biasing member

[0167] Arm of the biasing member

[0168] First arm of the biasing member

[0169] Second arm of the biasing member

[0170] Protrusion of the plate

[0171] Protrusion of the housing

[0172] First protrusion of the housing

[0173] Second protrusion of the housing

[0174] Ball spring

[0175] Clip

[0176] Axis of rotation of the motor

[0177] Axis of rotation of the driving gear

[0178] Clamping direction of the first brake pad assembly

[0179] Release direction of the first brake pad assembly

Claims

1. A braking system, the braking system comprises: (a) a brake caliper housing that supports a brake pad assembly connected to a piston; (b) an electric motor gear unit having an electric motor connected to a drive gear, wherein during a brake application operation or a brake release operation, the drive gear moves the brake pad assembly based on power received by the electric motor; and (c) a plate connected to the drive gear, wherein the plate generates a reverse driving force to move the drive gear during the brake release operation and thereby directly or indirectly move the brake pad assembly.

2. The braking system according to claim 1, wherein when an electric motor failure occurs, the reverse driving force generated by the plate is sufficient to retract the brake pad assembly from a rotor of a vehicle to reduce or eliminate the force applied by the brake pad assembly to the rotor.

3. The braking system according to claim 1 or claim 2, wherein the plate is adapted to rotate with the drive gear during the brake application operation, the brake release operation, or both.

4. The braking system according to any one of the preceding claims, wherein the plate is adapted to rotate independently of the drive gear during the brake application operation, the brake release operation, or both, or vice versa.

5. The braking system according to any one of the preceding claims, wherein the plate and the drive gear are coaxial.

6. The braking system according to any one of the preceding claims, wherein the drive gear includes a plurality of pins or protrusions extending from a surface of the drive gear, and the plurality of pins or protrusions interact with one or more fins extending from a surface of the plate.

7. The braking system according to claim 6, wherein the plurality of pins contact the one or more fins during the brake application operation, the brake release operation, or both, such that rotation of the drive gear causes rotation of the plate.

8. The braking system according to any one of the preceding claims, wherein the plate includes a biasing member, and the biasing member winds during the brake application operation such that during the brake release operation, the biasing member releases the reverse driving force to move the drive gear.

9. The braking system according to claim 8, wherein the biasing member includes a first arm fixed by a protrusion of the plate and a second arm that moves freely between a pair of stop points.

10. The braking system according to claim 8 or claim 9, wherein a first stop point is an initial position of the second arm before the biasing member winds, and a second stop point is a final position reached by the second arm when the biasing member has wound completely.

11. The braking system according to any one of claims 8 to 10, wherein when the second arm reaches the second stop point during the brake application operation, the plurality of pins of the drive gear deflect the one or more fins of the plate, thereby allowing the drive gear to continue rotating independently of the plate.

12. The braking system according to any one of claims 8 to 11, wherein, the biasing member is fixed around the axis of the plate.

13. The braking system according to any one of claims 8 to 12, wherein, the biasing member is located on the surface of the plate opposite to the surface including the one or more fins.

14. The braking system according to any one of claims 8 to 13, wherein, during the brake release operation, the reverse driving force is released by the biasing member so that the one or more fins of the plate rotate and contact the plurality of pins of the driving gear, thereby causing the driving gear to also rotate in the same direction as the plate.

15. The braking system according to any one of the preceding claims, wherein, the braking system includes a gear train between the motor and the driving gear, and the torque generated by the motor is transmitted to the driving gear through the gear train.

16. The braking system according to claim 15, wherein, the motor includes a motor output end connected to the gear train, and the rotation axis of the motor output end is parallel or perpendicular to the rotation axis of the driving gear.

17. The braking system according to any one of the preceding claims, wherein, the driving gear is connected to a ball and nut assembly such that during the brake application operation, the driving gear drives the ball and nut assembly to contact the piston, whereby the piston contacts the brake pad assembly to move the brake pad assembly towards the rotor of the vehicle.

18. The braking system according to any one of claims 12 to 17, wherein, the axis of the plate is fixed to the housing of the motor gear unit by a clip.

19. The braking system according to any one of claims 9 to 18, wherein, the pair of stop points are protrusions located on the housing of the motor gear unit.

20. The braking system according to any one of the preceding claims, wherein, the driving gear includes an output shaft extending from the surface of the driving gear, the output shaft outputs the power received by the motor to move the brake pad assembly, and the plate is positioned adjacent to the opposite surface of the driving gear.

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