Electromechanical brake device for a motor vehicle

Abstract

The present invention relates to an electromechanical brake device (1) for a motor vehicle, comprising an actuating device (5) which has at least one electric motor (41, 42) and to which a brake part (32) is operatively connected which can be adjusted along an adjusting direction (V) and can be brought into braking engagement with a corresponding brake part (2), wherein the motor (41, 42) can be activated by an electric control unit (100). In order to make reduced complexity and improved operation possible, the invention proposes that the actuating device (5) and the control unit (100) are of integrated configuration with the brake device (1).

Description

[0001] Electromechanical braking device for a motor vehicle

[0002] State of the art

[0003] The invention relates to an electromechanical braking device for a motor vehicle, comprising an actuating device which has at least one electric motor and to which a braking part is operatively connected, which braking part can be adjusted along an adjustment direction and can be brought into braking engagement with a counter-braking part, wherein the motor can be controlled by an electrical control unit.

[0004] Such a braking device of a motor vehicle is designed as a friction brake, in which a braking element supported on the chassis and fixed relative to the rotation of the wheel to be braked can be brought into braking engagement by means of an adjusting device with a counter-braking element that rotates with the wheel. During braking engagement, a frictional contact is created between the braking element and the counter-braking element, the so-called braking contact. The braking torque generated by friction increases the higher the adjusting force exerted by the adjusting device in the adjustment direction.

[0005] A common design is the well-known disc brake, in which the counter-braking component is formed by a brake disc rotating with the wheel and axially gripped on both sides by a brake caliper. By means of at least one, preferably linear, actuator axially supported on the brake caliper, a braking component, usually a brake pad, can be adjusted in an axial direction and thereby brought into frictional contact with an axial side of the brake disc. The brake disc is frictionally clamped in braking engagement between the adjusted braking component and another braking component supported axially opposite the brake caliper.

[0006] Each actuator has at least one electric motor that can be controlled by an electrical control unit to generate a braking intervention. In the prior art, for example, it is known from DE 195 37 464 A1 to control the motors of all braking devices assigned to the individual wheels to be braked using a central control unit of the motor vehicle. In principle, this enables the execution of manual and automated braking operations, whereby manual inputs and parameters dependent on the current operating and driving situation can be taken into account according to predetermined braking algorithms. To generate the braking forces specified in this way, the windings of the motors of all actuators are energized by the control unit via electrical supply lines that run from the braking devices to the control unit.However, the relatively long cable lengths required can increase susceptibility to failure. To ensure the high level of safety absolutely necessary for brake operation, a relatively high level of additional effort is required, for example, as mentioned in the cited prior art, through redundant design, control and monitoring devices, or similar measures.

[0007] In view of the problems explained above, it is an object of the present invention to enable reduced expenditure and improved operation in an electromotive braking device.

[0008] Description of the invention

[0009] This object is achieved according to the invention by the braking device according to claim 1. Advantageous further developments emerge from the subclaims.

[0010] In an electromechanical braking device for a motor vehicle, comprising an actuating device which has at least one electric motor and to which a braking part is operatively connected, which braking part can be adjusted along an adjustment direction and can be brought into braking engagement with a counter-braking part, wherein the motor can be controlled by an electrical control unit, it is provided according to the invention that the actuating device and the control unit are designed to be integrated with the braking device.

[0011] A braking device according to the invention comprises at least one electrical control unit and an electric brake actuator connected thereto with at least one actuating device. This actuator is assigned to a wheel to be braked, which wheel has a co-rotating counter-brake part, for example a brake disc. The friction surfaces of the brake disc can preferably be encompassed in a conventional manner by a brake caliper of the braking device which is stationary relative to the rotation of the wheel, which carries the actuating device and on which the braking part is supported to absorb the reaction force occurring during braking intervention. The braking surfaces on the braking and counter-brake parts preferably extend parallel to a braking surface plane, or braking plane for short, which extends normal or perpendicular to the adjustment direction.The control unit can preferably have a power supply for the motor and an electrical control circuit, which can be connected to the electrical control system of the motor vehicle for electrically controlling the brake, preferably via a bidirectional interface to a bus system of the vehicle control system. The control unit can have electrical inputs and / or outputs, for example for connecting sensors for detecting the wheel position and / or wheel speed, the position of the braking part, for detecting wear, and / or other parameters such as operating temperature or the like. The measured values ​​recorded by the sensors can be evaluated in the control unit and transmitted as measured data to the vehicle control system via the outputs.Alternatively or additionally, it is possible for the control unit to directly control the actuator independently of the central vehicle control system, for example, to set an optimal air gap width, to implement individual wheel anti-lock braking, or similar. This allows for advantageous decentralized control of operating functions.

[0012] According to the invention, the electrical control unit and the electromechanical actuating device can be combined into an integrated unit. According to the invention, the electrical control unit can be connected to a brake caliper, which also carries all electromechanical functional components. This allows a brake unit to be provided as a particularly compact unit.

[0013] A key advantage is that it can be easily installed in the limited space available in the wheel suspension area, so that a conventional hydraulic brake calliper can be replaced by an electromechanical braking device essentially without any design changes.

[0014] A further advantage is that the control unit can be located in the immediate vicinity of the motor, allowing short electrical supply and control lines to be implemented, which is beneficial for interference-free operation.

[0015] Furthermore, it is possible to implement decentralized safety functions assigned to each brakeable wheel, which can be activated independently of the central vehicle control system. For example, if overheating, which may indicate a malfunction, is detected, the assigned control unit can activate local emergency operation for the affected wheel. This allows for an increased level of safety, even in the event of a disruption in communication with the central vehicle control system.

[0016] It is advantageous for the control unit to be arranged in a control housing. The control housing can be structurally integrated with the braking device; for example, it can be fixed to the actuator or the brake caliper. Preferably, the control housing can be hermetically sealed, with the actual electrical control circuit protected inside and the connected electrical control and supply lines leading to the outside in a sealed manner.

[0017] A preferred embodiment can provide for the control unit to have a control board. The control board comprises a flat, extended printed circuit board made of an insulating material, on which the electrical components of the control unit are arranged and electrically interconnected. This allows for a compact and robust design. The control board's shape and dimensions can be easily adapted to the available installation space, allowing it to be housed, for example, in a control housing.

[0018] It is advantageous for the control board to be arranged perpendicular to the adjustment direction. The control board can be flat in the shape of a plate, for example by being mounted on a preferably flat circuit board. It can extend essentially normally, i.e. perpendicular to the adjustment direction, wherein the surface normal can have an angular deviation of + / - 15° to the adjustment direction. The arrangement normal relative to the adjustment direction implies that the control board is arranged essentially parallel to the braking plane, i.e. parallel to the braking surfaces of the braking element and the counter-braking element, for example parallel to the annular axial braking surfaces of a brake disc. This advantageously makes it possible for the braking device to be constructed to be relatively flat axially, i.e. measured in the adjustment direction.In this way, it can be ensured that the brake unit, which is mounted in the area of ​​the wheel suspension and pivots together with the wheel when steering, does not restrict the steering angle.

[0019] Preferably, the control unit comprises an electrical plug device with at least one plug connection. The plug connection serves to electrically connect the braking device to the control system of the motor vehicle. It is designed for connection to a corresponding electrical plug (connector), which in turn is connected to the supply or control lines. Each plug connection has a defined insertion direction in which it must be inserted into a corresponding plug connection to create an electrically conductive contact. The advantage is that the plug connectors enable a simple, easy-to-install connection of the braking device to the motor vehicle electrical system.

[0020] In the aforementioned embodiment, it is expedient for the connector device to have a plurality of plug-in connections. This allows, for example, one or more connections each for connection to the power supply and to control lines of the bus system (data line).

[0021] Preferably, two of the plug-in connectors each have one or more connections for the power supply. Preferably, one of the plug-in connectors is assigned to the first servomotor, and another of the plug-in connectors is assigned to the second servomotor.

[0022] It is preferably provided that the two plug connections for the servo motors have geometric distinguishing features from one another so that confusion during contact with the vehicle assembly can be excluded (Poka Yoke).

[0023] It is advantageous if the plug-in connections have a plug-in direction perpendicular to the adjustment direction. The plug-in direction describes the spatial direction in which an electrical plug (connector) must be moved in order to bring into contact with a corresponding plug-in connection. In the adjustment direction normal to the braking surface, i.e. perpendicular to the braking surfaces of the braking element and the counter-braking element, the plug-in direction is accordingly aligned parallel to the braking surface. The advantage achieved in this way is that a flat axial installation height is permitted, whereby the electrical connecting cables can be led out laterally from the steering area in which the wheel is moved when steering. This protects the connecting cables and makes it possible to achieve a relatively large steering angle without any problems. Preferably, all plug-in connections can have a plug-in direction perpendicular to the adjustment direction.

[0024] It is possible for the plug-in connectors to be aligned at an angle relative to each other with respect to their respective insertion direction. This enables a space-saving and installation-friendly arrangement.

[0025] The practical implementation of the aforementioned design can be achieved, for example, by arranging the plug-in connectors in a Y-shaped, T-shaped, cross-shaped, or star-shaped configuration with respect to their respective insertion directions. Preferably, the insertion directions of adjacent plug-in connectors are at an angle of at least 90° to each other. This allows for an easily accessible, assembly-friendly arrangement.

[0026] An advantageous embodiment can be realized in that the plug device has a one-piece carrier body (plug body). One or more plug connections adapted to receive corresponding plugs can be formed on the carrier body, also synonymously referred to as the plug body. The plurality of plug connections can preferably be individualized in such a way that a clear assignment to the corresponding plugs of the motor vehicle control lines is provided, according to the well-known "poka-yoke" design principle. The carrier body preferably has an insulating material or is formed entirely from such an insulating material. It can be made, for example, from a plastic, for example as an injection-molded part made of a thermoplastic polymer, preferably as a one-piece part.The electrical connection is established via electrical conductor elements that extend through the carrier body and are connectable to the control circuit at one end. At the other end, they may have contact pins or the like arranged in the region of the plug-in connector(s) so that they can be connected to a plugged-in plug. The conductor elements may comprise metallic wires, rails, or the like, which may be arranged in a non-detachable and sealed manner in the carrier body, for example, by overmolding with plastic using an injection molding process.

[0027] It is advantageous that the plug-in direction of the connectors is aligned parallel to a control board. This allows for a low overall height of the control unit while maintaining good accessibility to the connectors.

[0028] Preferably, the connector device can be fixed to a control circuit board. This allows for a compact, robust, and easy-to-assemble design. For example, it is possible for a carrier body of the connector device to be permanently connected to a circuit board, for example, by welding, riveting, gluing, or the like. This effectively protects the electrical connections between the connector and the control circuit against mechanical stress.

[0029] It can be provided that the braking device comprises an adjusting device and a braking part connected thereto, which can be adjusted by the adjusting device along an axis, i.e. in an adjustment direction, and can be brought into braking engagement with a counter-braking part, wherein the adjusting device has a first adjusting drive and a second adjusting drive coupled in series thereto, wherein the first adjusting drive has a first drive wheel that can be driven in rotation, and the second adjusting drive has a second drive wheel that can be driven in rotation and is coaxial with the first drive wheel, wherein a coupling device is arranged between the first drive wheel and the second drive wheel. It can be provided that the coupling device is designed as a friction clutch with a friction element that can be frictionally connected to a counter-friction element in coupling engagement.

[0030] In the following, the first and second drive wheels are referred to together as the two drive wheels or simply as the drive wheels.

[0031] The drive wheels can be designed as a gear, for example as a spur gear, or as a belt or toothed belt wheel or worm wheel, so that generally a gear wheel is provided via which a drive torque from an electric actuator can be coupled into the actuator.

[0032] A friction clutch can be implemented between the drive wheels. This comprises a friction element that is torque-locked to one of the drive wheels, and a corresponding counter-friction element that is torque-locked to the other drive wheel. The friction element can be brought into frictional engagement with the counter-friction element in any relative angular position. This creates a purely force-locking coupling, in contrast to the positive locking connection in the prior art. This allows the relative position of the drive wheels to be continuously specified, in contrast to the discrete locking steps in the prior art. Accordingly, a uniform, continuous adjustment of the second actuator relative to the first actuator is possible, and a continuous adjustment of the air gap can be achieved.This is particularly advantageous with regard to the consistent adjustment of the braking system's optimal operating point to the continuous wear of the braking component during operation, i.e., the continuous wear of the brake pad. Compared to the only step-by-step adjustment option in the prior art, a consistently improved braking system response can be achieved, thus increasing operational reliability and greater ease of use.

[0033] An advantage over a locking clutch described in the prior art is that, for the actuation and release of the clutch device, essentially no axial relative movement is required between the clutch elements engaged in the clutch, for example, between the drive wheels or the locking elements, which must necessarily be movable relative to one another to create and release the lockable positive connection. In contrast, the pure frictional connection between the friction and counter-friction elements according to the invention can be simply determined by the applied axial actuation force, whereby the friction and counter-friction elements do not need to be moved axially relative to one another. This enables a simpler and more reliable design of the clutch device.

[0034] It is preferably provided that the friction clutch has a defined, predeterminable clutch torque. The clutch torque indicates the maximum differential torque that can be transmitted force-lockingly between the friction element and the counter-friction element due to the frictional engagement during clutch engagement. If the clutch torque is exceeded, the clutch device slips, causing the two drive wheels to rotate relative to each other. One advantage of this is that the friction clutch according to the invention slips continuously in a sliding manner, enabling improved, uniform readjustment of the air gap. Furthermore, there is no need to design for axial evasive movements of locking elements, as is the case with the known locking clutch, and thus compensate for these.

[0035] It is advantageous for the friction element and the counter-friction element to be arranged coaxially. This coaxial arrangement corresponds to the coaxial arrangement of the drive wheels. The friction element and the counter-friction element can be arranged in a simple and compact design in the area of ​​the axially opposing end faces of the drive wheels. Due to the above-described generation of the pure frictional connection of the clutch, no moving parts are required, as is the case with the locking clutch in the prior art.

[0036] In an advantageous embodiment, it can be provided that the friction element and the counter-friction element are conical. The friction element can have a conical section that converges at least partially in the axial adjustment direction and has a conical friction surface, which can be designed as an outer cone or inner cone, and which has a corresponding conical section on the counter-friction element, which is designed in the opposite direction as an inner cone or outer cone and has a conical counter-friction surface. To generate the clutch engagement, the outer cone dips into the inner cone, with the conical friction and counter-friction surfaces being frictionally loaded against one another by an axial actuating force of the clutch. One advantage of this is that the cone can convert the axially acting actuating force of the clutch into the normal force acting between the conical friction surfaces in frictional contact.Thus, a flatter pitch allows a relatively small axial actuating force to be converted into a larger normal force in the frictional contact, whereby a high clutch torque can be achieved even with a relatively small axial actuating force of the clutch.

[0037] Alternatively or in addition to the aforementioned embodiment, the friction element and the counter friction element can be designed as planar surfaces. The corresponding friction surfaces are designed, at least in sections, as flat axial surfaces, similar to a disc clutch. This enables a space-saving arrangement, especially when only a relatively small clutch torque is to be achieved.

[0038] It can preferably be provided that the friction element and the counter-friction element are preloaded against each other. Preferably, the friction element and the counter-friction element are elastically or resiliently preloaded against each other. The friction and counter-friction surfaces are pressed against each other in frictional engagement with a predetermined axial preload force. To generate the preload force, an elastic preload element, for example a spring element or the like, can preferably be provided. The clutch torque of the friction clutch is determined by the actuating force acting perpendicular to the frictional contact, i.e. the force applied axially between the friction and counter-friction elements, whereby the clutch torque is greater the greater the preload force. This opens up the advantageous possibility of simply specifying the clutch torque through the preload force exerted by the preload element.For example, in the case of a spring element that is elastic in the axial direction, such as a compression spring, the applied preload force can be simply specified and adjusted by the spring constant and the compression of the spring.

[0039] The aforementioned embodiment can be advantageously implemented in that the friction element and / or the counter-friction element is axially displaceable and supported against the first drive wheel or the second drive wheel via an axially acting spring element. The friction element or the counter-friction element is connected to one of the drive wheels in a torque-locking and axially displaceable manner, for example via radially projecting drivers that create a positive connection effective in the circumferential direction. The spring element axially clamped between the friction element or the counter-friction element and one of the drive wheels, which spring is preferably designed as an axially acting compression spring, ensures that the friction or counter-friction element is axially preloaded against the corresponding counter-friction or friction element axially supported on the other drive wheel, i.e. is pressed axially against it in frictional contact.The corresponding counter friction element is rotationally connected to the other drive wheel. Alternatively or additionally, the counter friction element can be supported on one of the drive wheels via a spring element. An advantage of this arrangement is that the friction clutch according to the invention can be integrated between the drive wheels in a simple and space-saving manner.

[0040] In an advantageous development, it is possible for the friction element and / or the counter-friction element to be arranged in the first drive wheel or the second drive wheel. For example, it is possible to design one drive wheel essentially drum-shaped, so that the friction or counter-friction element can be arranged in an interior space enclosed by the rotating gear or gear ring. This enables a compact design that is protected against external influences. For example, the drive wheel of the first actuator can have a conical friction element that engages axially in a counter-friction element designed as an inner cone, which is arranged at least partially within the second drive wheel.

[0041] A particularly compact design can be achieved - especially in the last-mentioned embodiment - by arranging the drive wheels within the axial extension of the actuators, i.e. by not being mounted axially protruding on one side.

[0042] It is preferred that the friction element and / or the counter-friction element have a friction lining. The friction and counter-friction elements preferably have a metallic base body, for example, made of steel. To prevent metal-to-metal contact, a coating or lining can preferably be applied to create a friction pairing with a defined friction force, for example, made of sintered, metal and / or ceramic friction materials, composite materials, or the like. This ensures a defined, reproducible clutch torque.

[0043] An actuator can be provided with a spindle drive. In this case, a threaded spindle engages a spindle nut in a conventional manner, and a relative rotating drive is provided via a drive wheel connected to the threaded spindle or the spindle nut. It is possible for the spindle nut to form the drive-side drive element of the actuator, and the threaded spindle to form the output-side output element, which is linearly adjustable relative to it, or vice versa.

[0044] It is possible for an actuator to have a ball ramp arrangement, a wedge disk arrangement, or a tilting pin arrangement. In a ball ramp arrangement, also known as a ramp bearing, the drive and output elements preferably have cam disks with raceways or ramps inclined relative to the axis, between which balls that can roll in the circumferential direction are arranged. A relative rotation leads to the output element being axially displaced relative to the drive element due to the ball rolling on the ramps. In a tilting pin arrangement known per se, tilting pins are arranged between the drive and output elements and each supported in the circumferential direction in such a way that, depending on the direction of rotation, they are inclined more or less towards the axis during relative rotation, whereby the distance between the drive and output elements can also be adjusted.

[0045] In the actuating device, two similarly acting actuators can be combined as first and second actuators, for example, two spindle drives. It is also possible to combine two different designs, for example, a ball ramp arrangement as the first actuator and a spindle drive as the second actuator for adjusting the air gap. The respective characteristic properties of each design can be optimally utilized. For example, a ball ramp arrangement can be used to realize a non-linear adjustment characteristic with little effort, and / or self-locking properties at least in sections, and / or a defined dead center or extended position that enables a defined adjustment path.The realization of the positive properties mentioned may at least partially require a precise specification of the air gap, which is not possible with the locking clutch in the prior art, but can be easily realized by means of the friction clutch according to the invention.

[0046] In a method for operating an electromechanical braking device, which has an actuating device comprising a first actuating drive and an actuating drive coupled in series therewith, and which acts on a braking part that can be brought into braking engagement with a counter-braking part in the direction of an axis, wherein the first actuating drive has a rotatably drivable first drive wheel, to which a first drive torque can be applied for actuation, and the second actuating drive has a rotatably drivable second drive wheel coaxial with the first drive wheel, to which a second drive torque can be applied for actuation, wherein a clutch device is arranged between the first drive wheel and the second drive wheel, it can be provided that the clutch device is designed as a friction clutch and has a predeterminable clutch torque, upon exceeding which the first drive wheel slips slidingly relative to the second drive wheel,wherein, to actuate the first actuator, the first drive wheel and the second drive wheel are driven synchronously, so that the second actuator remains unactuated, and to actuate the second actuator, the second drive wheel is driven, and the first drive wheel is stopped relative thereto, so that the friction clutch slips and the first actuator remains unactuated.

[0047] The features mentioned above in connection with the braking device can be used individually and in combination to implement the method.

[0048] To adjust the first actuator, an actuating torque can be coupled into the first drive wheel by means of a first electric actuator motor, and accordingly the second actuator can be driven by a second electric actuator motor.

[0049] During normal braking operation, the first and second drive wheels rotate synchronously. This can be achieved by driving the first and second drive wheels with synchronized drive torques by the first and second actuators. Alternatively, the second drive wheel can be driven synchronously by the clutch device when the first drive wheel is driven, as long as the transmitted drive torque remains below the clutch torque. In this operating mode, the second actuator remains unactuated and rotates freely as a whole, together with the braking element.

[0050] In contrast to the prior art, the clutch device can slip continuously and smoothly when the clutch torque is exceeded to adjust the air gap. This can be achieved, for example, by immobilizing the drive wheel of the first actuator, for example, by a brake or a corresponding control of the first drive motor, while the second drive motor applies a second drive torque to the second drive wheel that is greater than the clutch torque. This rotates the second drive wheel relative to the first drive wheel, and by actuating the second actuator, the air gap can be continuously and sensitively adjusted, so that continuously advancing wear of the brake element or brake pad can be optimally compensated.

[0051] It is possible for the first drive wheel and the second drive wheel to be torque-locked by the friction clutch to generate a synchronous drive.

[0052] In this case, synchronous drive of the two drive wheels by the actuator motors is not required. Any torque differences can be compensated within specified tolerances. It can advantageously be provided that a higher clutch torque is specified when the first actuator is actuated than when the second actuator is actuated. The first actuator is actuated by synchronous drive of the first and second drive wheels. The friction element and the counter-friction element are preloaded against each other by the spring force of the spring element, and in addition, the adjusting force of the first actuator acts opposite to the spring force. This results in a relatively high clutch torque. If, on the other hand, only the second drive wheel is turned to adjust the air gap, the spring force alone acts, so that a lower clutch torque is set. This makes adjusting the air gap easier.

[0053] In the embodiments described above, the first actuator can preferably form a braking drive according to the function specified above, and the second actuator can accordingly form an adjusting drive.

[0054] Description of the drawings

[0055] Advantageous embodiments of the invention are explained in more detail below with reference to the drawings. In detail:

[0056] Figure 1 shows a braking device according to the invention in a schematic perspective view,

[0057] Figure 2 is a side view of the braking device according to Figure 1,

[0058] Figure 3 shows the adjusting device according to the invention of the braking device according to Figure 1 in a schematic perspective view,

[0059] Figure 4 shows a section QQ through the braking device according to Figure 1,

[0060] Figure 5 shows the first actuator of the braking device according to Figure 1 in a schematic perspective view,

[0061] Figure 6 is an enlarged detailed view of the adjusting device from Figure 4, Figure 7 is an isolated schematic perspective view of a control unit according to the invention,

[0062] Figure 8 shows a further view of the control unit according to Figure 6,

[0063] Figure 9 is an isolated, enlarged perspective detail view of the plug device of the control unit according to the invention,

[0064] Figure 10 is a schematic cut-out view of a conductor arrangement of the plug device according to Figure 9.

[0065] Embodiments of the invention

[0066] In the various figures, identical parts are always provided with the same reference symbols and are therefore usually named or mentioned only once.

[0067] Figure 1 shows a braking device according to the invention as a whole, designed as a disc brake. This comprises a brake disc 2, which forms a counter-braking part within the meaning of the invention and is connected to a vehicle wheel (not shown here) that is rotatable about a wheel axis R. A brake caliper 3 engages the two axial end faces of the brake disc 2.

[0068] Brake disc 2 is designed as a non-ventilated brake disc made of solid material. Alternatively, it can also be designed as an internally ventilated brake disc.

[0069] An electric brake actuator 4 according to the invention is attached to the brake caliper 3, which is shown in Figure 3 in a separate, isolated schematic perspective view and is explained in detail in Figures 4 to 6.

[0070] The brake actuator 4 comprises an adjusting device 5 which extends axially in the direction of an axis A which is parallel to the wheel axis R and indicates the adjustment direction V of the adjusting device 5.

[0071] As can be seen in the sectional view of Figure 4 along axis A, the brake disc 2 is arranged axially between two brake pads 31 and 32. One brake pad 31 is firmly supported on the brake caliper 3 on the side facing away from the brake actuator 4. The other brake pad 32, which forms a braking part within the meaning of the invention, is attached to the adjusting device 5 and can be adjusted by it in the axial adjustment direction V defined by the axis A to generate the braking engagement on the brake disc 2, as indicated by the arrow in Figure 4.

[0072] In the unactuated state of the braking device 1, there is an axial air gap L between the brake disc 2 and the adjustable brake pad 32, which is shown schematically in Figure 4 as exaggeratedly wide.

[0073] The structure of the adjusting device 5 is shown in Figure 4 and in the enlarged section thereof in Figure 6.

[0074] The actuating device 5 comprises a first actuating drive 6, which has a ramp bearing, and a second actuating drive 7, which is axially (with respect to the axis A) serially coupled thereto and has a spindle drive.

[0075] The first actuator 6, which in the example shown is designed as a ramp bearing, comprises a drive-side cam disc 61 and an output-side cam disc 62, which are axially and rotationally fixedly supported on the brake actuator 4. Balls 63 are arranged between the cam discs 61 and 62. As can be seen in the schematically isolated view of Figure 5, the cam discs 61 and 62 have axially opposite, ramp-like raceways 64, which are inclined to the axis A and between which balls 63 can roll. A rotation of the output-side cam disc 62, in Figure 5 above, relative to the fixed drive-side cam disc 61 - as schematically indicated by the curved arrows - leads to a linear adjustment of the output-side cam disc 62 in the adjustment direction V parallel to the axis A. As a result, the brake pad 32 can be brought into braking engagement by actuating the first actuator 6, as shown in Figure 4.

[0076] The cam disc 62 is connected to a coaxial gear 65, which is designed as a spur gear and forms a drive wheel in the sense of the invention.

[0077] The gear 65 is in gear engagement with a first electric actuator 41. This enables the rotating drive of the cam disk 62 and thus actuation of the first actuator 6. The second actuator 7, which in the example shown is designed as a spindle drive, has a threaded spindle 71 on the output side, which engages in the internal thread of a drive-side spindle nut 72. This internal thread is formed in the output-side cam disk 62 of the first actuator 6, so that the functions of the output-side cam disk 62 and the drive-side spindle nut 72 are combined in one component.

[0078] The threaded spindle 71 is connected via a hub part 74 to a coaxial gear 75, which is axially fixed and rotatably mounted in the brake actuator 4. The threaded spindle is coupled to the gear 75 in a torque-locking but axially displaceable manner via drivers 73, which may, for example, have radially projecting projections or teeth that engage axially displaceably in axial slots of the hub part 74.

[0079] Like gear 65, gear 75 can be designed as a spur gear and is arranged coaxially adjacent to it. This gear 75 is in gear engagement with a second electric actuator 42. This enables the rotating drive of the threaded spindle 71 and thus the actuation of the second actuator 7.

[0080] The threaded spindle 71 is axially connected via a thrust bearing 43, for example, an axial roller bearing as shown, to a thrust piece 44, to which the movable brake pad 32 is attached, as can be seen in Figure 4. The thrust piece 44 can also be referred to as a piston.

[0081] The clutch device according to the invention comprises a friction element 8, which is designed as a coaxial, conical extension extending from the cam disc 62 toward the second actuator 7. The conical extension has a conical friction surface 81 arranged externally on an outer cone. The friction element 81 can preferably be formed integrally with the cam disc 62 / spindle nut 72.

[0082] In clutch engagement, the friction element 8 is frictionally coupled to a counter friction element 9. The conical projection axially engages a corresponding conical opening of the counter friction element 9, which has a conical friction surface 91 arranged in an inner cone. In clutch engagement, the friction surface 81 and the counter friction surface 91 are in frictional contact with each other, as can be clearly seen in Figure 6.

[0083] The counter friction element 9 is coupled to the gear 75 in a torque-locking but axially displaceable manner via drivers 92, which engage axially displaceably in corresponding slots 76 in the hub part 74 or the gear 75. A spring element 93 is arranged between the gear 75 or the hub part 74 connected thereto and the counter friction element 9. Due to its axially effective spring force, the counter friction element 9 is elastically braced against the friction element 8. This generates a defined clutch torque of the friction clutch according to the invention formed by the friction element 8 and the counter friction element 9.

[0084] The second embodiment, shown in the same view as in Figure 6, differs in the design and arrangement of the friction surface 81 and the counter friction surface 91, both of which are designed as flat axial surfaces, in contrast to the conical surfaces of the first embodiment according to the first embodiment shown in Figures 4 and 6. The functionality is essentially identical, and therefore the same reference numerals are used.

[0085] To actuate the braking device 1, the gears 65 and 75 rotate synchronously, causing the first actuator 6 to execute a working stroke in the adjustment direction V, causing the brake pad 32 to pass through the air gap L and engage the brake disc 2. The synchronous drive of the gears 65 and 75 can be achieved by synchronizing the drive speeds of the actuator motors 41 and 42, or by driving only one of the actuator motors 41 or 42, while the other actuator motor 42 or 41 runs idle. The frictional coupling engagement between the friction element 8 and the counter friction element 9 then ensures synchronous rotation of the gears 65 and 75.

[0086] To adjust the width of the air gap L, the gear 65 is fixed or blocked, for example, by appropriately controlling the first servomotor 41. The second servomotor 42 rotates the gear 75 relative to the gear 65, causing the friction clutch to slip continuously. Accordingly, the second actuator 7 is adjusted evenly, allowing the width of the air gap L to be continuously adjusted and adapted, for example, to compensate for wear on the brake pad 32.

[0087] Because the friction element 8 and the counter-friction element 9 are arranged entirely or at least partially within the gears 65 and 75, a particularly compact design can be achieved. The braking devices shown in Figures 1 to 7 are designed as floating-caliper brakes, also referred to as floating-caliper brakes. The brake pad 32 is pressed against the brake disc 2 by the pressure piece 44, and the brake pad 31 is pressed against the brake disc 2 by the brake caliper 3, which is displaceable relative to the brake disc 2 in the direction of the axis A. Alternatively, the solution according to the invention can also be used with a fixed-caliper brake.

[0088] In the embodiments according to Figures 1 to 6, the first actuator 6 forms a braking drive or working drive in the sense of the method according to the invention, and the second actuator 7 correspondingly forms an adjusting drive.

[0089] According to the invention, the brake actuator 4 has an integrated control unit 100. This is arranged in a control housing 101, which is connected to the brake caliper 3.

[0090] In Figure 7, the control housing 101 is shown separately, in a perspective view oblique to the axis A.

[0091] The electrical control circuit of the control unit 100 is constructed on a circuit board 102 which is enclosed in the control housing 101 and is shown separately in Figure 8 in a schematic perspective view.

[0092] The plate 102 is flat and extends normal to the axis A or to the adjustment direction V. Thus, it extends parallel to a braking plane which is parallel to the end faces of the brake disc 2.

[0093] The control housing 101 encloses the circuit board 102 and extends parallel to it, i.e. also normal to the axis A. It is axially, i.e. in the direction of the axis A (= adjustment direction V), relatively flat, as can also be clearly seen in Figures 1 and 2.

[0094] On the outer side facing away from the brake caliper 3, an electrical connector device 103 is mounted on the circuit board 102. This connector device has three plug connections 104. Each plug connection 104 has a defined insertion direction E, in which a corresponding electrical plug (connector) (not shown here) of a control or supply line of the motor vehicle electrical system or bus system must be inserted into a corresponding plug connection to create an electrically conductive contact. The insertion direction E is indicated by an arrow. In the preferred embodiment shown, the insertion directions E of all plug connections 104 run parallel to the surface extension of the circuit board 102, and thus perpendicular to the axis A.In the example shown, the plug connections 104 are arranged in a T-shape, as can be clearly seen in Figure 7, with the insertion directions E being at an angle of at least 90° to one another. Two of the plug connections 104 preferably have both conductor elements 107 for supplying voltage to the servo motors 41, 42 and conductor elements 107 for data transmission. The third plug connection preferably has only conductor elements 107 for data transmission. The data transmission can, for example, be a signal relating to the rotor position of the servo motors 41, 42 or a value determined therefrom by the control unit, such as the position of the actuating device 5.

[0095] Figure 9 shows a schematic cut-out view of the plug device 103. This has a plug body 105 made of an insulating material, which can comprise a one-piece plastic part, preferably a plastic injection-molded part, on which all plug connections 104 can be integrated.

[0096] The connector body 105 can have fixing elements 106, which can, for example, have pins, screw-in openings, locking elements, or the like, which enable a connection to the circuit board 102. Preferably, the fixing elements 106 can also be formed integrally with the connector body 105, for example, as thermally compressible rivet pins or the like.

[0097] For electrical connection, the plug device 103 has conductor elements 107 which extend from the plug terminals 104 through the plug body 105 and are electrically connected to the control circuit on the side facing the circuit board 102.

[0098] The conductor elements 107 preferably comprise sheet metal and / or wire molded parts, as shown schematically in Figure 10. These can be arranged in the illustrated orientation in the connector device 103 according to Figure 9, for example, permanently embedded by overmolding in the plastic injection molding.

[0099] The control circuit mounted on circuit board 102 is connected to motors 41 and 42 via supply lines U, which are shown schematically in Figure 8. List of reference symbols

[0100] 1 braking device

[0101] 100 control unit

[0102] 101 Control housing

[0103] 102 circuit board

[0104] 103 Plug device

[0105] 104 plug connection

[0106] 105 connector body

[0107] 106 Fixing element

[0108] 107 Ladder element

[0109] 2 brake discs

[0110] 3 brake caliper

[0111] 31, 32 brake pad

[0112] 4 Brake actuator

[0113] 41 , 42 Actuator

[0114] 43 thrust bearings

[0115] 44 Pressure piece

[0116] 5 Adjusting device

[0117] 6 first actuator (brake drive)

[0118] 61 cam disc

[0119] 62 cam disc (integrated with spindle nut 72)

[0120] 63 ball

[0121] 64 Career

[0122] 65 gear

[0123] 7 second adjusting drive (adjusting drive)

[0124] 71 threaded spindle

[0125] 72 spindle nut (integrated with cam disc 62)

[0126] 73 drivers

[0127] 74 Hub part

[0128] 75 gear

[0129] 76 slot

[0130] 8 Friction element

[0131] 81 Friction surface

[0132] 9 Counter friction element

[0133] 91 Counter friction surface

[0134] 92 drivers

[0135] 93 Spring element A axle

[0136] R wheel axle

[0137] V Adjustment direction

[0138] L Air gap E Insertion direction

[0139] U supply line

Claims

PATENT CLAIMS 1. Electromechanical braking device (1) for a motor vehicle, comprising an actuating device (5) which has at least one electric motor (41, 42) and to which a braking part (32) is operatively connected, which braking part is adjustable along an adjustment direction (V) and can be brought into braking engagement with a counter-braking part (2), wherein the motor (41, 42) can be controlled by an electrical control unit (100), characterized in that the actuating device (5) and the control unit (100) are designed to be integrated with the braking device (1).

2. Braking device according to claim 1, characterized in that the control unit (100) is arranged in a control housing (101).

3. Braking device according to one of the preceding claims, characterized in that the control unit (100) has a control board (102).

4. Braking device according to one of the preceding claims, characterized in that the control board (102) is arranged perpendicular to the adjustment direction (V).

5. Braking device according to one of the preceding claims, characterized in that the control unit (100) has an electrical plug device (103) with at least one plug connection (104).

6. Braking device according to claim 5, characterized in that the plug device (103) has a plurality of plug connections (104).

7. Braking device according to one of the preceding claims 5 to 6, characterized in that the plug connections (104) have a plug-in direction (E) perpendicular to the adjustment direction (V).

8. Braking device according to one of the preceding claims 5 to 7, characterized in that the plug connections (104) are angularly aligned relative to one another with respect to their respective insertion direction (E).

9. Braking device according to claim 8, characterized in that the plug connections (104) are arranged in a T-shaped, cross-shaped, or star-shaped manner with respect to their respective insertion direction (E).

10. Braking device according to one of the preceding claims 5 to 9, characterized in that the plug device (103) has a carrier body (105).

11. Braking device according to one of the preceding claims 5 to 10, characterized in that the insertion direction (E) of the plug-in connections (104) is aligned parallel to a control board (102).

12. Braking device according to one of the preceding claims 5 to 11, characterized in that the plug device (103) is fixed to a control board (102).

Images