Disc brake system

Abstract

The invention relates to a disc brake system having a brake disc packet (1) with a number of inner discs (3) and a number of outer discs (2), wherein either the number of inner discs or the number of outer discs are connected, more particularly for conjoint rotation, to a rotating shaft (31) for the transfer of a torque, and the respective other of the number of inner discs or the number of outer discs are connected, more particularly for conjoint rotation, to a fixed brake anchor (29), wherein at least some of the inner discs (3) or outer discs (2) are designed as friction discs and at least some of the respective other of the inner 3 and outer discs 2 are designed as counter-discs, and the brake disc packet 1 has at least some inner (3) and outer discs (2) arranged alternately and is supported at least partially in an axially movable manner, and a brake actuator (19) is provided which is suitable for exerting an axial force on the (brake disc packet 1) such that by way of an at least partial frictional connection between friction discs and counter-discs an operative connection between the shaft (31) and the brake anchor (29) can be established such that the shaft (31) can be braked.

Description

[0001] MULTI-DISC BRAKE SYSTEM

[0002] The invention relates to a multi-disk brake system with a brake disc pack having a number of inner discs and a number of outer discs, wherein either the number of inner discs or the number of outer discs are connected to a rotating shaft for transmitting torque, in particular in a rotationally fixed manner, and the other of the number of inner discs or the number of outer discs are connected to a stationary brake anchor, in particular in a rotationally fixed manner, wherein at least the inner discs or the outer discs are at least partially designed as friction discs and the other of the inner and outer discs are at least partially designed as counter discs, and the brake disc pack has at least partially alternately arranged inner and outer discs and is mounted at least partially for axial movement, and a brake actuator is provided which is suitable for exerting an axial force on the brake disc pack,so that an operative connection between the shaft and the brake armature can be established by at least partial frictional engagement between the friction plate and the counter plate, so that the shaft can be braked.

[0003] With electric vehicles, there is a growing need to make them even more environmentally friendly. Research is being conducted into additional vehicle components for this purpose. Conventional braking systems generate significant amounts of particulate matter, which is particularly harmful because toxic components can endanger human health.

[0004] Various technical solutions are known from the prior art that have advanced the state of the art in this direction. For example, publication AT520430B 1 discloses a vehicle with an electric drive that features a brake that emits few of these dangerous particles. The disclosure of this publication is hereby incorporated in its entirety into the present application. In practice, this brake has proven to be too inefficient. It is complex in design and too expensive for use in conventional vehicles, and it does not respond quickly enough to braking impulses from the driver and / or a self-driving system.

[0005] JP2009150486A discloses a multi-disk brake for a vehicle. It teaches an automatic adjustment mechanism for a hydraulic actuation system. Drag losses have proven to be a particular problem with such braking systems.

[0006] Another problem is the inertia of such brakes.

[0007] In order to realize braking systems that are technically efficient and meet the corresponding requirements, including, for example, environmental compatibility, it is necessary to further improve the known braking systems from the state of the art.

[0008] It is therefore an object of the present invention to develop a more efficient braking system according to the preamble of claim 1.

[0009] The inventive problem is solved by claim 1.

[0010] Alternative solutions are shown which, individually or in combination, solve the basic problem.

[0011] The fact that only a portion of a friction plate is actuated by an actuation system and / or the active portion of a friction plate itself is limited results in a variety of advantages. Drag torques of such a brake can be reduced, and the inertia of such a brake is also reduced. A faster response of such a braking system is thus technically possible. This makes it easier to combine fast-acting systems with such a brake. Furthermore, this design is energy-efficient and can reduce parasitic energy losses, for example, due to undesirable or excessive friction.

[0012] According to a special embodiment of the invention, only one part of the friction plate is effective, or more effective, than another part of the friction plate. This can be achieved, for example, by only one area of ​​the friction plate being designed with a friction lining, or by one part of the friction plate having more lining (in terms of lining thickness) than another lining, or by the friction plate consisting of friction lining segments. According to a special embodiment, one area of ​​the friction plate becomes effective, or more effective, than another area of ​​the friction plate due to the special type of actuation, for example, by an actuator that only presses against the plate pack in segments.The situation is that the area of ​​the friction plate that overlaps with the segment-like actuator in the axial direction, particularly the actuation direction of the multi-disk brake, is naturally more effective for frictional contact between the friction plate and the counter-plate than, for example, an area of ​​the friction plate that does not overlap with the segment-like actuator in the axial direction, particularly the actuation direction of the multi-disk brake. Combinations of the various embodiments are also encompassed by the present invention.

[0013] According to a particular embodiment of the invention, a multi-disk brake system is provided with a brake disc pack having a number of inner discs and a number of outer discs, wherein either the number of inner discs or the number of outer discs are connected, in particular in a rotationally fixed manner, to a rotating shaft for transmitting torque. The other of the number of inner discs or the number of outer discs are connected, in particular in a rotationally fixed manner, to a stationary brake anchor, wherein at least the inner discs or the outer discs are at least partially designed as friction discs and the other of the inner and outer discs are at least partially designed as counter discs. The brake disc pack has at least partially alternating inner and outer discs and is mounted at least partially for axial movement.A brake actuator is provided which is suitable for exerting an axial force on the brake disc pack so that an operative connection between the shaft and the brake anchor can be established by an at least partial frictional engagement between the friction disc and the counter disc, so that the shaft can be braked.

[0014] According to a particular embodiment, the brake actuator has a contact surface for contacting the brake disk pack, which, based on an axial projection, only partially covers, in particular less than 70%, preferably less than 50%, particularly preferably less than 35% of the mean surface of the annular contour of the brake disk pack, in particular the surface of the annular contour of the first counter or friction disk of the brake disk pack adjacent to the brake actuator.

[0015] According to further possible embodiments of the invention, the brake actuator has a contact surface for contacting the brake disk pack, which, based on an axial projection, only partially covers, in particular less than 60%, preferably less than 40%, particularly preferably less than 30% or less than 25% of the mean surface of the annular contour of the brake disk pack, in particular the surface of the annular contour of the first counter or friction disk of the brake disk pack adjacent to the brake actuator.

[0016] According to a particular embodiment of the invention, a solution was devised during the development of an emission-free multi-disk brake system for automotive applications that enables a particularly technically efficient solution. Previous multi-disk brake systems always used full-surface annular pistons for actuation or activation. Due to the expected high dynamics when activating driver assistance systems, problems can arise with annular piston systems, particularly the failure to achieve the required actuation dynamics or the high cost of doing so.

[0017] This has the disadvantage that the brake assistance systems known today, such as the start-off assistant and the parking brake function, are very complex to transfer to a ring piston actuation.

[0018] According to a special embodiment, the requirements of modern driving dynamics systems can be implemented in a technically efficient manner by using a modified known brake caliper technology, since the displacement volume, for example of the hydraulic actuation system, is significantly reduced.

[0019] According to a special embodiment, a brake actuator is used as a so-called segment actuator to actuate a multi-disk brake.

[0020] According to a particular embodiment of the invention, the brake actuator, preferably a brake caliper, is designed with a segment-shaped brake piston that can be electrically and / or hydraulically delivered to the brake disc assembly. Furthermore, a counterholder that interacts with the brake piston is provided at the end of the brake disc assembly axially opposite the brake piston.

[0021] According to a particularly preferred alternative or additional embodiment of the multi-disk brake system, the brake actuator is designed in a pincer-like configuration, particularly as a brake caliper. The pincer-like design of the brake actuator, similar to known disc brake actuators, for example, on motorcycles, makes it possible to achieve rapid actuation and response of the braking system with a multi-disk friction brake. In this way, multi-disk brakes, especially encapsulated ones, can be used for further applications in the field of fast-acting car brakes.

[0022] According to a particularly preferred embodiment of the multi-disk brake system, the pincer-shaped brake caliper is mounted in a floating manner, and a first movable actuating element of the brake actuator is provided on the first side of the brake disc pack, so that this actuating element can be advanced against the brake disc pack and exerts the axial force on the brake disc pack. Furthermore, a counterholder opposite the first actuating element is provided at the end of the brake disc pack axially opposite the first actuating element and is designed such that, upon actuation of the first actuating element, a reaction force oriented opposite to the axial force is generated at the counterholder. Preferably, the counterholder, in turn, exerts the reaction force against the brake disc pack, particularly preferably through a floating design that advances the counterholder against the brake disc pack and / or presses it against the brake disc pack.

[0023] According to a particular embodiment, the brake actuator, preferably as a brake caliper, is designed with a segment-shaped brake piston that can be electrically and / or hydraulically delivered to the brake disk set, and a counter-holder that cooperates with the brake piston is provided at the end of the brake disk set axially opposite the brake piston.

[0024] According to a particular embodiment of the invention, the brake actuator has at least one, preferably at least two, hydraulic cylinders for actuating the brake piston.

[0025] According to a particular embodiment of the invention, two or more brake actuators are provided and the sum of the associated contact surfaces for contacting the brake disk pack relative to an axial projection covers only partially, in particular less than 70%, preferably less than 50%, particularly preferably less than 35%, of the mean surface of the ring or disc contour of the brake disk pack, in particular the mean surface of the disc or ring contour of the first counter or friction plate of the brake disk pack adjacent to the brake actuator.

[0026] According to a particular embodiment of the invention, at least one of the inner plates, preferably a plurality of the inner plates, is designed as a friction plate and the friction plate has a friction layer on a carrier material.

[0027] According to a particular embodiment of the invention, at least one of the outer plates, preferably a plurality of the outer plates, is designed as a friction plate and the friction plate has a friction layer on a carrier material.

[0028] According to a particular embodiment of the invention, the friction plate has friction lining segments on its contact surface for contacting the counter plate, which segments are interrupted by at least one area that has no friction lining or less friction lining.

[0029] According to a particular embodiment of the invention, the friction plate has friction lining segments on its contact surface for contacting the counter plate, which is interrupted by at least one area that has no friction lining or less friction lining, and / or the friction plate is formed by several independent friction plate segments, wherein the friction plate segments are mounted, preferably independently of one another, for example on the brake anchor or brake basket.

[0030] These friction plate segments replace the friction plate at the axial position of the plate pack, creating clearance between the friction plate segments compared to a single-piece friction plate. This also saves weight and minimizes unwanted energy losses.

[0031] According to a particular embodiment of the invention, the friction plate is designed to be stationary and a coolant supply is provided between the stationary friction plate and an adjacent rotating steel plate in at least one area which has no friction lining and / or less friction lining and / or a free space between the friction plate segments into which the friction plate is interrupted.

[0032] According to a particular embodiment of the invention, several separate injectors, in particular coolant lances, are provided as the coolant supply, which convey the coolant, in particular oil, at several points between the plates of the brake plate package.

[0033] This special design of the friction plates and their friction lining, or the special design of the friction plate as a discontinuous friction plate, resulting in multiple friction plate segments, makes it possible to provide particularly efficient cooling. Cooling lines can be provided in the resulting spaces, supplying a suitable coolant and thus enabling efficient cooling management of the brake plate. For example, a cooling fluid, such as cooling oil, can be supplied to the counter plates, particularly steel plates or plates made of other highly conductive materials, using lance-shaped devices.

[0034] According to a particular embodiment, a coolant distributor, for example an oil lance, is provided in an intermediate space of the disk pack, in particular in the region of a friction disk which has no or less friction lining and / or, if friction disk segments form the friction disk, in the free space between the friction disk segments, adjacent to a counter-disk, so that coolant, for example oil, can be conveyed to the counter-disk.

[0035] According to a particular embodiment of the invention, the friction plate has a friction layer on a carrier material which comes into contact with one of the counter plates when the brake is activated, wherein the friction layer only partially covers, in particular less than 70%, preferably less than 50%, particularly preferably less than 35% of the average surface of the disc or ring contour of the friction plate based on an axial projection. Here, too, contact is understood to mean the active contact of the surface, for example through segmentation or action by the actuator in the axial direction. Other areas of the friction plate can come into contact with the counter plate, but have a significantly smaller contribution to the frictional engagement, in particular based on an equal surface area of ​​15%, 25%, 35% or 50% less. These other areas have a different geometric design, in particular free spaces, or have comparatively fewer and / or no friction lining.

[0036] According to a particular embodiment of the invention, the position of the friction layer on the friction plate overlaps with the position of the contact surface of the brake actuator in axial projection by at least 50%, preferably by at least 60%, particularly preferably by at least 70%, so that the axial force of the brake actuator when the brake is activated can establish contact between the counter plate and the friction plate in the area of ​​the friction layer.

[0037] According to a particular embodiment of the invention, at least one of the counter-lamellae, preferably a plurality of the counter-lamellae, comprises a material with good thermal conductivity, for example steel and / or aluminum, and has an average axial thickness of at least 2 mm, preferably more than 3 mm, particularly preferably more than 4 mm.

[0038] According to a particular embodiment of the invention, the brake disc package is arranged in a housing, for example by seals and / or built-in filters, in such a way that the number of particles of brake dust that enter the environment during operation of the multi-disk brake system can be minimized.

[0039] According to a particular embodiment of the invention, the multi-disk brake system, the brake disc package is arranged in a housing, for example by seals and / or built-in filters, so protected that the number of particles of brake dust that enter the environment during operation of the multi-disk brake system can be minimized, in particular below a limit value of 3 mg / km, in particular below 2 mg / km, preferably below 1.5 mg / km, based on the distance traveled by a vehicle in which the multi-disk brake system is integrated.

[0040] According to a particular embodiment of the invention, the brake disc package is arranged in a preferably closed housing - preferably in a reduction gear of an electric drive - so that - technically speaking - no particles of brake wear enter the environment.

[0041] According to a particular embodiment of the invention, the multi-disk brake is provided to brake an axle and / or half-axle of a vehicle.

[0042] According to a particular embodiment of the invention, the brake disc package is arranged in a preferably closed housing so that the number of particles of brake dust that enter the environment during operation of the multi-disk brake system can be minimized.

[0043] According to a particular embodiment of the invention, the brake disc assembly is arranged in a preferably closed housing, so that the number of brake dust particles released into the environment during operation of the disc brake system can be minimized to 7 mg / km, preferably 3 mg / km for a vehicle or for the vehicle's disc brake system. The specified values ​​refer to particles with a size of PMio.

[0044] According to a particular embodiment of the invention, at least a number of the friction plates, in particular all friction plates, are designed to be fixed and at least a number of the counter plates, in particular all counter plates, are designed to be rotatable with the shaft to be braked.

[0045] According to a particular embodiment of the invention, the brake disc package and / or the brake actuator or segment actuator is mounted floating in the housing.

[0046] According to a particular embodiment of the invention, the brake disc pack is positioned concentrically on the shaft to be braked.

[0047] According to a particular embodiment of the invention, a liquid cooling medium and a cooling system are provided which enables the cooling medium to be supplied to the brake disk pack.

[0048] According to a particular embodiment of the invention, the brake actuator has a parking and / or holding brake, which can be activated in particular via an electric drive.

[0049] For a better understanding of the invention, it is explained in more detail in a non-limiting manner with reference to the following figures. Each of them shows a simplified, exemplary, schematic representation:

[0050] Fig. 1 an exemplary brake disc package in oblique view

[0051] Fig. 2 an example outer disc of the brake disc package

[0052] Fig. 3 an example inner disc of the brake disc package

[0053] Fig. 4 the exemplary arrangement of the brake disc package in an E-axle

[0054] Fig. 5 is a detailed view of an exemplary embodiment of a non-limiting embodiment of the invention. Fig. 6 is a detailed view of an exemplary embodiment of a non-limiting embodiment of the invention according to Fig. 5.

[0055] Fig. 7 is a detailed view of another exemplary embodiment of a non-limiting embodiment of the invention

[0056] Fig. 8 is a detailed view of an exemplary embodiment of a non-limiting embodiment of the invention according to Fig. 7

[0057] Fig. 9 is an installation view of an exemplary embodiment of a non-limiting embodiment of the invention according to Fig. 7

[0058] Fig. 10 is a detailed view of another exemplary embodiment of a non-limiting embodiment of the invention

[0059] Fig. 11 is a detailed view of an exemplary embodiment of a non-limiting embodiment of the invention according to Fig. 10

[0060] Fig. 12 is an installation view of an exemplary embodiment of a non-limiting embodiment of the invention according to Fig. 10

[0061] Fig. 13 a schematic view of a plate and the contact surface of the brake actuator

[0062] Fig. 14 a schematic view of a cooling solution for a possible embodiment of a brake disc pack

[0063] Fig. 15 a schematic view of a counter plate or steel plate with a friction plate formed by friction segments

[0064] By way of introduction, it should be noted that in the variously described embodiments, identical parts are provided with identical reference numerals or identical component designations, whereby the disclosures contained in the entire description can be transferred mutatis mutandis to identical parts with identical reference numerals or identical component designations. The position information chosen in the description, such as top, bottom, side, etc., also relates to the directly described and illustrated figure, and these position information are to be transferred mutatis mutandis to the new position in the event of a position change. Figs. 1 to 3 show a brake disk pack 1, an outer disk 2 and an inner disk 3 of the brake disk pack 1. The brake disk pack 1 has a plurality of outer disks 2 and a plurality of inner disks 3, which can also be referred to as brake disks. The outer disks 2 are arranged alternately with the inner disks 3 in an axial direction 4.Via a corresponding actuating mechanism, the inner plates 3 are adjustable relative to the outer plates 2 in the axial direction 4, so that a frictional connection is formed between the inner plates 3 and the outer plates 2. The inner plates 3 have an at least approximately annular base body 5 with a first surface 6 and a second surface 7 opposite this in the axial direction 4. At least one friction lining 8 is arranged on each of the first and / or second surfaces 6, 7. The inner plates 3 are therefore so-called lining plates. However, it is also possible for the inner plates 3 not to have any friction linings 8.

[0065] The friction linings 8 can be designed according to the prior art. The outer plates 2 also have an at least approximately annular base body 9, which, however, is free of friction linings. The outer plates 2 are therefore the so-called counter-plates, which can be brought into frictional engagement with the friction linings 8 of the inner plates 3. However, it is also possible for friction linings 8 to be arranged on one of the two surfaces 10, 11 of the outer plates 2, particularly if no friction linings 8 are arranged on the inner plates 3. The friction lining(s) 8 can be formed by sintered friction linings or resin-bonded friction linings, as are known in principle for friction plates from the prior art. The counter-plates can be made of steel or aluminum, etc. Likewise, the base body of the inner plates can be made of steel or aluminum, etc. The inner plates 3 are connected in a rotationally fixed manner to a first component, for example, a shaft.For this purpose, the inner plates 3 can have radially inwardly projecting projections 12 on a radially inner end face, which engage in corresponding recesses in the first component. The outer plates 2 are connected in a rotationally fixed manner to a second component, which can be a housing, for example. For this purpose, the outer plates 2 can have radially outwardly projecting projections 13 on a radially outer end face, which can engage in corresponding recesses on a radially inner surface of the second component. The brake plate pack 1 is part of a brake plate friction system in a vehicle (not shown). This vehicle, in addition to the brake plate pack 1, also has an electric motor as its drive. This electric motor can be the main drive (electric car) or an auxiliary drive (hybrid car).

[0066] Fig. 4 schematically shows that at least one brake disc pack 1 is arranged on the drive shaft 31 of an electric axle drive 15 of the motor vehicle. In particular, this embodiment variant shows brake disc packs 1 arranged downstream of the differential 16 of the motor vehicle and acting, for example, on the left and right drive shafts 31. The differential 16 is connected to an electric motor 17. The brake disc packs 1 can be encapsulated in housings 14 that prevent particles from escaping into the environment.

[0067] Fig. 5 shows a multi-disk brake system 18. This system shows a brake disc pack 1 which is arranged in a brake cage 29. A brake actuator 19 acts on the brake disc pack 1. The brake actuator has, for example, a hydraulic cylinder (not shown in detail) with the aid of which it is suitable for axially advancing a piston 20 onto the brake disc pack 1 and thus establishing the frictional connection in the brake disc pack 1. Such a piston can be actuated hydraulically, electrically, pneumatically or in another way. The brake actuator 19 acts on the brake disc pack 1 via the piston via a contact surface 21. The brake actuator shown in Fig. 5 also has an electric drive via which an electrically activated parking and / or handbrake can be implemented.For this purpose, an electric motor 22 and an actuating device 23 are schematically provided, which, for example, also acts on the piston 20 and the contact surface 21. Of course, this electric parking and / or holding brake can also be provided independently of the main brake system. The multi-disk brake system 18 has a counter-holder 28. This counter-holder 28 counteracts the axial force of the piston. As schematically shown, the brake cage 29 can be designed as a pincer-shaped or saddle-shaped device.

[0068] Fig. 6 shows a schematic axial view of the brake disc pack 1. The effective contact surfaces 21 (dashed line) on the brake disc pack 1 are shown schematically. These are the intersections of the piston surfaces 24 (solid line) of the brake actuator 19 with the piston contact surface on the disc 27 of the brake disc pack 1 adjacent to the brake actuator. Thus, the brake actuator 19 acts in the axial direction on the brake disc pack via this contact surface 21. Fig. 6 shows that two brake actuators 19 are provided on opposite sides of the brake disc pack 1. The hydraulic cylinders 26 and the mountings 25 of the brake actuators 19 are shown in dashed lines. As can be seen from Fig.6 shows the contact surface 24 (=sum of the contact surfaces); only a small portion of the total surface of the plate 27 or the brake plate package 1 available for activation acts on the axial force of the brake actuators 19, in this case less than 20%.

[0069] Fig. 7 shows an alternative embodiment of a multi-disk brake system 18. It shows a brake disc pack 1 arranged in a housing 29. A brake actuator 19 acts on the brake disc pack 1. The brake actuator has a hydraulic cylinder suitable for axially advancing a piston 20 against the brake disc pack 1 and thus establishing frictional engagement in the brake disc pack 1. As can be seen, a hydraulic cylinder 26 for receiving the hydraulic fluid or hydraulic medium (connection of the cylinder for supplying hydraulic fluid not shown) is provided on the side of the piston 20 facing away from the brake disc pack 1. The brake actuator 19 acts on the brake disc pack 1 via the piston 20 via a contact surface 21 and brings the discs into frictional engagement. The piston 20 presses against the counterholder 28.Of course, a suitable mechanism for resetting the piston or other brake actuator must be provided; such mechanisms are known to the person skilled in the art.

[0070] Fig. 8 shows a schematic axial view of another exemplary brake disk pack 1. The effective contact surfaces 21 (dashed line) on the brake disk pack 1 are shown schematically. These are the intersections of the piston surfaces 24 (solid line) of the brake actuator 19 with the feed surface of the piston on the plate 27 of the brake disk pack 1 adjacent to the brake actuator. The brake actuator 19 thus acts in the axial direction on the brake disk pack via this contact surface 21. Fig. 6 shows that two brake actuators 19 are provided on opposite sides of the brake disk pack 1. The hydraulic cylinders 26 and the fastenings 25 of the brake actuators 19 are shown in dashed lines. On the right-hand side, a brake actuator 19 with two hydraulic cylinders 26 is shown. As can be seen from Fig.8 shows the sum of the contact surfaces 24, via the axial force of the brake actuators 19 on the brake disc pack 1, only a small proportion of the total surface of the disc 27 or the brake disc pack 1 available for activation acts, in this case less than 20%.

[0071] Fig. 9 shows a schematic view of a multi-disk brake system 18 according to a configuration similar to Fig. 5. The brake disc set 1 has friction discs (shaded) as inner discs, which are connected to the drive shaft 31 via a gear 30. The drive shaft 31 is connected, for example, to a wheel of the vehicle on the left side and to a differential on the right side (both not shown for the sake of clarity). The outer discs (shaded), which are designed, for example, as steel discs, are connected to the stationary brake anchor or brake basket 29. As can be seen from the schematic drawing, the multi-disk brake system 18 is floatingly mounted in the housing 14 via a bearing 32.

[0072] 10 to 12 show an embodiment in which the outer plates 33 are designed as friction plates and are connected, for example, to the stationary bearing 32. The inner plates 34, on the other hand, are designed as counter plates to the friction plates, for example as steel plates, and are connected to the gear 30. This embodiment is particularly advantageous when only certain areas of the friction plates actually have a friction lining 35. Such an embodiment is shown in more detail in Fig. 11. Since the friction plates are stationary, it is possible, for example, that the friction lining is only provided in the area, viewed axially, which corresponds to the effective contact surface of the brake actuator 19, i.e., viewed axially, the brake actuator presses axially onto the brake plate in the area in which a friction lining is also provided. Of course, these areas can also only partially overlap. As can be seen from Fig.It is also possible for the friction plate to be broken down into individual friction plate segments, which are, for example, mounted separately from one another at suitable bearing points or guides 32. Fig. 11 schematically shows two brake actuators 19, each with two hydraulic cylinders. In this illustration, the friction lining 35 of the friction plate is shown in dashed lines. The piston surface of the brake actuator protrudes slightly beyond the brake lining of the friction plate. The friction plate, or one of the two friction plate segments shown, is also inm, which makes the plate carrier and the friction lining clearly visible.

[0073] To illustrate the invention, Fig. 13 shows an axial view of a simplified plate 36, as a friction plate or just a friction plate segment, which has a friction lining 35. For reasons of clarity, the toothing of the plate is not shown. For example, it is a friction plate with external toothing that is fixedly arranged in the plate pack, while the steel plate arranged opposite the friction plate rotates with the shaft to be braked. Other designs are conceivable. In the form shown, the brake lining 35 is only designed as a segment brake lining. Furthermore, a brake actuator 19 is shown. This has, for example, a brake piston 37, the piston surface 38 of which is shown. As can be seen from Fig. 13, the piston surface 38 only partially covers the brake lining 35.In the area of ​​overlap, which is further highlighted by a border 39, the piston acts on the plate (in this case on a friction surface). This surface is defined as the contact surface 40. According to other embodiments, this surface has no friction lining and is designed, for example, as part of a steel plate, for example as a counter plate. The contact surface 40 to the entire surface of the plate 36, i.e. the entire axial surface of the ring contour or the ring surface of the plate 36 (including the contact surface, as can be seen in the plane of the drawing in Fig. 13), which is in principle available for axial contact by the brake actuator or its piston, corresponds to a certain percentage. In the illustrated embodiment, the proportion of the contact surface 40 to the total surface of the plate is less than 30%.Of course, it is possible to insert any plate between the brake actuator and the first plate, not primarily marked as a plate. In this case, too, the brake actuator, via this intermediate plate, acts only on the contact surface of the first plate adjacent to the brake actuator in the axial projection.

[0074] According to a particular embodiment of the invention, it is conceivable for the surface of at least individual plates to have a crown, for example a convex design. This crown is particularly advantageous in the region of the axial contact surface, so that better and faster contact between the brake piston and the brake plate pack is possible. In this way, for example, the plate adjacent to the brake actuator and / or the plate adjacent to the counterholder can have such a crown. Particularly preferably, a fixed plate of the brake plate pack is crowned, preferably this is the first plate adjacent to the brake actuator and / or the first plate of the brake plate pack adjacent to the counterholder.

[0075] Fig. 14 shows a schematic view of a preferred embodiment of a possibility for cooling a multi-disk brake. For this purpose, a plate 36 is shown. The plate has friction linings 37 and serves as a friction plate. For the sake of clarity, the teeth of the brake plate are not shown. For example, it is a friction plate with external teeth that is fixedly arranged in the plate pack, while the steel plate arranged opposite the friction plate rotates with the shaft to be braked. Other designs are conceivable. The schematic drawing shows a reservoir for a coolant, in particular a cooling oil. For this reason, the reservoir is referred to as an oil reservoir 42. However, other cooling media are also encompassed by the invention. The coolant is conveyed by a pump 43 via corresponding lines 44 to so-called lances, in particular oil lances 44.In the present case, two oil lances are shown, but any number of lances is possible. Designs other than lances are also possible. These oil lances are arranged in the spaces on the friction plate in the plate areas without friction lining 41. In the case of friction plate segments, more space is available for the oil lance because the entire space between the inner plates 34 is available. Thus, if the oil lance is very narrow, it can be arranged in the space between the part of the friction plate without lining and the adjacent steel plate, or in the case of friction plate segments, it can be larger because the entire space between the adjacent counter plates or steel plates is available. The rotating adjacent steel plate (not shown) distributes the coolant without causing high drag losses in the multi-disk brake.

[0076] Fig. 15 shows a further schematic view of a section of a multi-disk brake.

[0077] The plate 47 is a counter plate, for example a steel plate, which is arranged in a ring shape with a recess in the center along the axis of the multi-disk brake. The plate 47 has a toothing 48, which can be seen in the detailed view, which shows a detail of the arrangement in a section along the axis of the multi-disk brake. Here, several plates 47 are shown, which are arranged, for example, alternately with the friction plates. Corresponding representations can be seen in the other schematic figures in the application. Via this toothing 48, the plate 47 is directly or indirectly connected to the machine element to be braked. This can be, for example, a rotating shaft in the drive or chassis area of ​​a vehicle. As can also be seen in Fig. 15, a friction plate is provided which has two independently mounted friction segments 49.The two friction segments 49 of the friction plate are shown both together with plate 47 and in detail. Each segment 49 has a friction lining 50. According to a special embodiment, such a friction lining 50 is arranged on one or two sides of a carrier 51, for example a supporting plate. The friction segments are mounted in a rotationally fixed manner on corresponding guides. Such guides or bearings 32 are shown as examples in Fig. 10 and Fig. 12. As can be seen, a total of four such bearings or guides are required for the two friction segments 49. The friction segments are arranged so as to be displaceable but not rotatable. The friction segments 49 have suitable openings 52 for this purpose, in particular holes provided in ear-shaped projections of the supporting plate.Via a suitable actuating element, in particular a suitable piston, which is controlled, for example, mechanically, electrically, hydraulically and / or pneumatically, the friction segments with their friction linings are pressed against opposing plates, for example against plate 47, thereby braking the rotating plate 47. Figure 7 shows a simplified and schematic representation of the circular cylinders 54 of a hydraulic actuating system in a projection. As shown schematically in a further detailed view, coolant distributors 53, for example oil lances 45, protrude between the plates. The coolant distributors 53 are shown only schematically without a supply.

[0078] Reference symbol list

[0079] Brake disc package 32 bearing

[0080] Outer slat 33 outer slats

[0081] Inner slat 34 inner slats

[0082] Axial direction 35 friction lining

[0083] Base body 36 slats

[0084] Surface 37 brake piston

[0085] Surface 38 piston surface

[0086] Friction lining 39 border

[0087] Base body 40 contact surface

[0088] Surface 41 disc area without friction lining

[0089] Surface 42 Oil reservoir

[0090] Vorsprung 43 oil pump

[0091] Projection 44 oil lines

[0092] Housing 45 oil lance

[0093] E-axis 46 oil lance openings

[0094] Differential 47 disc

[0095] Electric motor 48 gearing

[0096] Multi-disk brake system 49 friction segments

[0097] Brake actuator 50 friction lining

[0098] Piston 51 carrier

[0099] Contact surface 52 Openings electric motor 53 Coolant distributor

[0100] Actuating device

[0101] Piston surfaces

[0102] Fasteners

[0103] hydraulic cylinder

[0104] slat

[0105] Counterholder

[0106] Brake basket / brake anchor

[0107] gear

[0108] drive shaft

Claims

P a t e n t a n s p r ü c h e 1. A multi-disk brake system of a vehicle with a brake disc pack having a number of inner discs and a number of outer discs, wherein either the number of inner discs or the number of outer discs are connected to a rotating shaft for transmitting torque, in particular in a rotationally fixed manner, and the other of the number of inner discs or the number of outer discs are connected to a stationary brake anchor, in particular in a rotationally fixed manner, wherein at least the inner discs or the outer discs are at least partially designed as friction discs and the other of the inner and outer discs are at least partially designed as counter discs, and the brake disc pack has at least partially alternately arranged inner and outer discs and is mounted at least partially for axial movement, and a brake actuator is provided which is suitable for exerting an axial force on the brake disc pack,so that an operative connection between the shaft and the brake anchor can be established by an at least partial frictional engagement between the friction plate and the counter-plate, so that the shaft can be braked, wherein the multi-disk brake system is designed such that in at least one of the friction plates, only a part of the surface of the friction plate opposite the next counter-plate - effectively or more effectively than the portion of the remaining surface of the friction plate - contributes to the frictional engagement with at least one of the counter-plates as an active friction surface, and this is achieved in that, • the brake actuator acts only on a part of the at least one friction plate, so that the brake actuator has a contact surface for contacting the brake plate package, which, based on an axial projection, only partially covers, in particular less than 70%, preferably less than 50%, particularly preferably less than 35% of the average surface of the disc or ring contour of the brake plate package, in particular the surface of the disc or ring contour of the first counter or friction plate of the brake plate package adjacent to the brake actuator, and / or • at least one of the friction plates has a friction lining as a segment, so that the friction plate has a contact surface with respect to the nearest counter-plate when the brake is activated, which contact surface is only partially, in particular less than 70%, preferably less than 50%, particularly preferably less than 35% of the mean area of ​​the discs or ring contour of the nearest counter-disk is covered and / or the brake actuator is designed in the form of a pliers, in particular as a brake caliper.

2. Multi-disk brake system according to claim 1, characterized in that the pincer-shaped brake caliper is mounted in a floating manner and a first movable actuating element of the brake actuator is provided on the first side of the brake disk pack, so that this actuating element can be advanced against the brake disk pack and exerts the axial force on the brake disk pack, and a counter-holder opposite the first actuating element is provided on the end of the brake disk pack axially opposite the first actuating element and is designed such that when the first actuating element is actuated, a reaction force oriented opposite to the axial force is generated at the counter-holder, preferably the counter-holder in turn exerts the reaction force against the brake disk pack, particularly preferably by a floating design, the counter-holder is advanced against the brake disk pack and / or pressed against the brake disk pack.

3. Multi-disk brake system according to one of the preceding claims, characterized in that the brake actuator, preferably as a brake caliper, is designed with a segment-shaped brake piston that can be delivered electrically and / or hydraulically to the brake disc pack, and a counter-holder that cooperates with the brake piston is provided at the end of the brake disc pack axially opposite the brake piston.

4. Multi-disk brake system according to one of the preceding claims, characterized in that two or more brake actuators are provided and the sum of the assigned contact surfaces for contacting the brake disc pack based on an axial projection only partially, in particular less than 70%, preferably less than 50%, particularly preferably less than 35%, of the mean surface of the ring or disc contour of the brake disc pack, in particular the mean surface of the disc or ring contour of the first counter or friction disc of the brake disc pack adjacent to the brake actuator, covers.

5. Multi-disk brake system according to one of the preceding claims, characterized in that at least one of the outer discs, preferably a plurality of Outer plates are designed as friction plates and the friction plate has a friction layer on a carrier material.

6. Multi-disk brake system according to one of the preceding claims, characterized in that the friction plate has friction lining segments on its contact surface for contacting the counter-plate, which is interrupted by at least one area which has no friction lining or less friction lining, and / or the friction plate is formed by several independent friction plate segments, wherein the friction plate segments are mounted, preferably independently of one another, for example on the brake anchor.

7. Multi-disk brake system according to claim 6, characterized in that the friction plate is designed to be stationary and a coolant supply is provided between the stationary friction plate and an adjacent rotating steel plate in at least one area which has no friction lining and / or less friction lining and / or a free space between the friction plate segments into which the friction plate is interrupted.

8. Multi-disk brake system according to claim 7, characterized in that several separate injectors, in particular coolant lances, are provided as the coolant supply, which convey the coolant, in particular oil, at several points between the discs of the brake disc pack.

9. Multi-disk brake system according to one of the preceding claims, characterized in that the friction plate has a friction layer on a carrier material which, when the brake is activated, comes into contact with one of the counter-disks at the contact surface, wherein the friction layer, based on an axial projection, only partially covers, in particular less than 70%, preferably less than 50%, particularly preferably less than 35%, the central area of ​​the disc or ring contour of the opposite counter-disk.

10. Multi-disk brake system according to claim 9, characterized in that the position of the friction layer on the friction disc overlaps with the position of the contact surface of the brake actuator in axial projection at least partially, in particular to at least 50%, preferably to at least 60%, particularly preferably to at least 70%, so that the axial force of the brake actuator when the brake is activated ensures contact between the counter-disk and Friction plate can be manufactured in the area of ​​the friction layer.

11. Multi-disk brake system according to one of the preceding claims, characterized in that the brake disc package is arranged in a housing, for example by seals and / or built-in filters, so protected that the number of particles of brake dust that enter the environment during operation of the multi-disk brake system can be minimized, in particular below a limit value of 3 mg / km, in particular below 2 mg / km, preferably below 1.5 mg / km, based on the distance traveled by a vehicle in which the multi-disk brake system is integrated.

12. Multi-disk brake system according to one of the preceding claims, characterized in that the brake disc package and / or the brake actuator is floatingly mounted in the housing.

13. Multi-disk brake system according to one of the preceding claims, characterized in that at least a number of the friction plates, in particular all friction plates, are designed to be stationary and at least a number of the counter-disks, in particular all counter-disks, are designed to be rotatable with the shaft to be braked.

Images