Drum brake that compensates for lateral offset of brake shoes

Abstract

The present invention relates to a drum brake (1) for an electric braking system of a motor vehicle, in which an actuator means, e.g., a geared motor drive module with a gear stage, preferably a rotary-to-translational converter, a transmission means, and optionally an expansion device (2) supported on an abutment (3), is in the force flow with movably mounted drum brake shoes (7, 8) suitable for and intended to cooperate with a brake drum (5). The present invention addresses the problem of further improving the efficiency, i.e., the force flow, of a drum brake (1), preferably electromechanically actuated, so that simple, fast, and accurate electric brake control, combined with simple actuator control, is possible throughout the entire wear-prone service life of the brake shoes, reducing complexity. To solve this problem, the present invention provides compensation for lateral offset, for example, by providing a joint disc / joint socket-type bearing geometry manufactured with special geometric profiling, so that a friction lining support geometry further developed with profiling that allows mutual articulation, resulting from the offset, is realized such that lining displacement perpendicular to the expansion direction is prevented or at least reduced.

Description

[Technical Field]

[0001] The present invention relates to a drum brake for motor vehicle braking systems, preferably electrically, in particular in particular electrohydraulically or electromechanically actuable, with actuator means, for example a geared motor drive module with a gear stage, transmission means and an extension device or abutment support of a rotation-to-translation converter in the force flow with a movably mounted drum brake shoe suitable for and designed to cooperate with the brake drum. [Background technology]

[0002] The prior art discloses hydraulically actuated drum brakes with actuator means, typically manufactured as hydraulic wheel cylinders, that enable the application of brake force to cooperating brake shoes and thus to the brake drum via an actuating element (hydraulic piston) (see, for example, page 129 of "Bremsenhandbuch" ["Brake Handbook"] ISBN 3-89059-008-x; 9th edition, 1986). Unfortunately, conventional hydraulic drum brakes are not as such suited to perform all the new closed-loop control tasks with the precision required in modern electronically closed-loop controlled drivetrain / brake systems, without maintenance, and over the life of the vehicle.

[0003] DE 10 2018 215 979 A1, by the same applicant as the present application, relates to an expansion device for expanding brake shoes of drum brakes for motor vehicles, in which a rotary-driven idle travel compensation device with a spring-loaded, rotatable readjusting screw is integrated into the expansion device. Summary of the Invention [Problem to be solved by the invention]

[0004] There is a need for further improvements in the relevant prior art, as there are no more advanced and practical solutions that allow adequately and completely addressing the effects of friction lining wear in modern automotive drum brake systems. [Means for solving the problem]

[0005] This object has been achieved for the first time by the present invention, very surprisingly, in a patentable and even more advantageous manner, by the combination of features as set forth in claim 1, in which a brake shoe lateral offset compensator is arranged adjacent to the extender and / or abutment in the interior space of the brake drum, said lateral offset compensator being integrated into the force flow of the drum brake laterally adjacent to the extender and / or abutment. In the context of this disclosure, features that are "lateral" relative to the lateral axis Q always mean that they are arranged orthogonally, i.e. at right angles, to the extension axis S of the extender 2. Although the present disclosure, in a simplified form by way of example, only refers to the arrangement of the compensator in the region of the extender, this does not constitute a limitation; rather, the compensator may equally be integrated into the lateral force flow in the region of the abutment, and it is very particularly preferred to provide a combination as shown in the embodiment according to the drawings.

[0006] It is particularly preferred that the advantageous lateral offset compensator is directly integrated so as to fit into the interface between the expander and the brake shoe. If accepted or required by the customer, in case of adaptive changes, an indirect integration of the compensator can be easily retrofitted by fitting via at least one interchangeable adapter component additionally integrated into the force flow without departing from the concept underlying the invention.

[0007] In one advantageous refinement, the compensation device has an articulated or movable bearing arrangement in its contact area, particularly based on an articulated positive guide. For this purpose, a two-dimensionally curved, arcuate track guide can be implemented in accordance with the joint disc / joint socket model. For the purpose of particularly economically manufacturing the joint-type curved (track) guide, it is advantageous for the contact geometry to further include at least one or more arc segments. Here, the paired radii of the paired arc segments that come into contact with each other advantageously have different curvatures for intimate contact with each other. In a preferred embodiment, the radii located on the actuating element side are dimensioned slightly smaller than the radii located on the brake shoe side when compared to each other. Considered relatively, in this case, the radius on the actuating element side can be dimensioned to approximately fall within the range of the brake drum diameter, while the corresponding radius on the brake shoe side can approximately fall within the range of 1 / 5 to 1 / 10 of the brake drum diameter. It is self-evident that close contact with one another has the highly advantageous side effect of contributing to an improvement in the ability of the contact pressure prevailing in the force flow to be transmitted through the mated components.

[0008] In a further improved embodiment of the invention, in order to increase effectiveness, it is further possible, i.e. advantageous if necessary, for the centre of one or more of the relevant joint radii to be shifted to some extent in the direction of the rotation axis of the wheel by a certain predetermined offset, which further advantageously contributes to suppressing the lateral offset induced by wear.

[0009] In summary, the present invention is based on a systematically planned study of drum brake system relationships, combined with the new realization that further measures beyond clearance compensation are considered necessary and advantageous for modernizing drum brakes. This is because the virtually unavoidable and entirely non-uniform drum brake shoe wear of the leading and trailing brake shoes, combined with the substantially uniform concentric wear pattern of the brake drum, over the system's service life results in a significant lateral offset of the force-transmitting bearing points relative to adjacent components (actuating elements, extenders, abutments) that are usually non-displaceable and / or arranged fixedly on the backplate. This, in turn, results in a certain degree of wear-induced lever arm change that must be taken into account from the perspective of closed-loop control. Furthermore, the wear-induced offset relative to the extenders can, to a certain extent, generate opposing force couplings, which can result in the introduction of lateral forces into the wheel brake drivetrain. The solution according to the present invention is based on the above-mentioned research results, and therefore, logically, the drum brake according to the present invention is advantageously equipped with the lateral offset compensation according to the present invention.

[0010] In a preferred exemplary embodiment, the offset compensation implemented comprises a joint disk-like / joint socket-like bearing geometry manufactured with a special geometric profiling in the indirect or direct contact between the actuating element and the brake shoe, and the further developed compensation according to the invention by the friction lining support bearing geometry has the very pleasing effect of helping to prevent or at least reduce displacement movements induced by the progression of wear in the support bearing by the support bearing design with a geometric profile. According to the invention, the wear offset compensation is automatic, does not involve electric current, and is compensated automatically, which in particular also improves the closed-loop control function and in particular the efficiency and force flow of the preferably electromechanically actuated drum brake.

[0011] The present invention is therefore generally suitable for use in all automotive braking systems having at least one drum brake. Here, the wheel brakes, particularly drum brakes, can be configured to be electrically, particularly electrohydraulically and / or electromechanically, actuated by an electronic control unit (ECU). In particular, the present invention, through mechanical design, allows the currently preferred electric brake-by-wire system, in conjunction with actuation by a simple electric actuator, to easily provide simple, fast, and highly accurate electric closed-loop brake control throughout the service life of the drum brake's wearable brake shoes. As a result, the present invention advantageously perfectly complements regenerative dry braking systems, which operate flexibly and in tandem as required. It is by no means essential that a vehicle braking system be equipped exclusively with drum brakes; rather, a mixed installation combining one or more brake types, particularly disc brakes, is possible and essentially intended. Here, it is advantageous, but by no means essential, that the various brake types of the vehicle braking system be paired to the same type on each axle. Departures from these principles are possible in special cases, such as may be related to brakes integrated into the drive train.

[0012] The present invention is very particularly suitable for combination with a braking system comprising drum brake load sensor means fixed to an anchor plate within the brake drum adjacent the compensator.

[0013] Further features and details of the invention that may relate to advantageous exemplary embodiments of the invention configured in any desired combination according to the entire content of the present disclosure will become apparent from the dependent claims in conjunction with the description based on the following drawings.

[0014] The drawings are in most cases in sketch form / schematically / by way of example. [Brief explanation of the drawings]

[0015] [Figure 1] The wear-induced lateral offset / "displacement" at the contact point of the support bearing on a (approximately half-scale) drum brake shoe with a gently rounded support bearing is shown by way of example: the trailing brake shoe 7 (with respect to the preferred direction of rotation U) is laterally offset very significantly at its support bearing / contact point (lateral offset Y1a / Y1b) over the service life of the friction lining considered (for example, approximately 7.9 / approximately 7.5 mm). [Figure 2] It will now be shown by way of example how the compensation means / support bearing profiling ("shell-disc design") according to the invention can be used to improve the lateral offset on a drum brake. Over the service life of the friction lining, the lateral offset at the support bearing contact point of the trailing brake shoe 7 results in approximately a quarter reduction, i.e. the displacement movement is reduced, for example, to approximately 1.77 / 1.91 mm with respect to the initial design as in FIG. 1. As will further be appreciated by those skilled in the art, in a particularly advantageous design according to the invention, the centre of the radius of the associated lining shoe is offset from its starting point by a distance Y1c / Y1d. [Figure 3-4] Another further development according to the invention is shown as an exemplary embodiment. This includes a variant with an offset of Y1c / Y1d relative to the axis Rk (shown in a new, unworn state in FIG. 3). Due to this offset, the contact point is located Y1a / Y1b above said axis "Rk". When the lining wears more and is at its maximum, the contact point moves to Y1'a / Y1'b on the axis center of Rk (see FIG. 4). Due to this offset, the maximum distance (Y1a, Y1b, Y1'a, and Y1'b) relative to the axis of Rk is approximately half that shown in FIG. 2. [Figure 5] For example, based on detail V of FIG. 2, a support bearing with geometrically implemented lateral offset compensation is shown by way of example. DETAILED DESCRIPTION OF THE INVENTION

[0016] The present invention generally relates to a drum brake 1 designed according to the invention for a motor vehicle, or to an electronic braking system having one or more drum brakes 1. This may generally be an electric service brake system designed to be released when de-energized, or an electric parking brake system designed to provide parking when de-energized, as well as combinations based on a combination of a parking brake system and a service brake system.

[0017] In this connection, the schematic diagram generally shows a drum brake 1, which, by way of example and for the sake of simplicity, is a special simplex-type drum brake and is therefore shown as a simple service brake. For simplicity's sake, the drawing does not show a parking brake device, but a parking brake could in principle be added and provided to provide parking when de-energized. Finally, further types of brakes (e.g., dual servo, duplex, dual duplex) are also in principle possible from a design perspective.

[0018] For actuation, the drum brake 1 preferably has an extension device 2 on its front side. The extension device 2 can be hydraulically and / or electromechanically actuated and has at least one, preferably two, actuating elements 15, 16. The actuating elements 15, 16 are translationally displaceable relative to the anchor plate 4 and the abutment 3. The actuating element and the abutment are fixed to the front side F of the anchor plate 4, respectively. The anchor plate 4 has its components and mounting portions fixed to it, and in particular may have an electromechanical wheel brake actuator on its rear side. The electromechanical wheel brake actuator can be actuated for each wheel and fixed relative to the anchor plate 4 so as to be non-rotatably fixed relative to the vehicle as a wheel brake actuating device. Brake shoes 7, 8 are also movably mounted on the anchor plate 4. The brake shoes 7, 8 cooperate with brake drum pots 6 of the brake drum 5, which are arranged fixedly relative to the wheels, i.e., they are rotatable relative to the anchor plate 4. Each brake shoe 7, 8 has a substantially rigid carrier for a friction lining 9, 10, which is shown as gradually worn, and a restoring spring 11, 12 may also generally be elastically preloaded and tensioned between the brake shoes 7, 8 to provide a restoring force to the brake shoes 7, 8 or to hold the brake shoes 7, 8 in an unactuated end position (starting from an unworn, unactuated starting point "0").

[0019] The invention is based on the recognition that wear of the friction lining in cooperation with the brake drum, which is always uneven for technical reasons, leads in conventional drum brakes to a geometric lateral offset in the region of the support bearing contact points 13, 13', 14, 14', as a result of which the support bearing contact points are displaced laterally, so to speak, perpendicular to the extension axis S of the actuating elements 15, 16 of the expander 2. Therefore, due to the increased lateral offset of the support / contact points of the brake shoes 7, 8 relative to one another in the region of the expander 2 and the abutment 3, a force coupling can occur, with the undesirable consequence that the expander 2 is not relieved of lateral forces, i.e., a torque is introduced, resulting in a gradually increasing lateral force load acting on the force flow of the expander 2. The invention improves this and makes it possible to compensate for the lateral forces or mitigate their adverse effects.

[0020] In the case of electric drum brakes, the electromechanical geared motor drive is designed so that each drum brake can generally be provided with an individually associated electromechanical wheel brake actuator means for closed-loop control of each wheel, although it is also possible for multiple drum brakes to have a common electromechanical actuator via a Bowden cable. A central electronic control unit may be provided for powering / activating / closed-loop control of the actuator means, and it is also possible for each wheel brake module to have a local electronic control unit, which may be interlinked with further electronic control units. The drum brake 1 may have force sensor means.

[0021] The advantage of the present invention is that it identifies and proposes an advantageous and simple solution in conjunction with electric drum brakes that solves the problem that occurs in known prior art drum brakes, where, during wear (from a new lining to a completely worn lining), the contact point that the brake shoe makes with the expansion unit moves significantly along the contact line, resulting in a large lever arm centered on the axial center of the expansion unit (see also Figure 1). Furthermore, for example, in electromechanically actuated drum brakes, an optimized design has not been realized with regard to the central introduction of forces from the brake shoe to the expansion unit.

[0022] The present invention aims to remedy these drawbacks by introducing the force as centrally as possible through the lining. Due to the more central force transmission, piston jams and increased friction, which can occur in conventional hydraulic brake drum cylinders (and lead to increased residual torque), are prevented or reduced. This results in a higher efficiency of the expansion unit. This favorable force introduction from the lining to the expansion unit is particularly useful in the case of electromechanical expansion units (e.g., ball screw or ball ramp systems). In addition to increasing efficiency, lateral forces can be absorbed due to the shorter guide length. This results in smaller dimensions for the electromechanical expansion unit. A further advantage is improved detection of values at the force transmission point by a correspondingly designed displacement / force measuring unit, which is preferably used, for example, in "dry" brake systems for brake torque monitoring. Here, lateral forces, for example, result in lateral deflections that falsify the measurement.

[0023] In the case of the "contact design" pursued here for the force contact point from the drum brake lining to the expansion unit, the "shell-disk design" significantly reduces the displacement of the lining (see also Figure 3). This configuration must be selected to keep the unavoidable lateral forces as small as possible and to support them in a favorable manner. In the case of embodiments with an additional "offset", the "start point" of the contact surface is displaced beyond the axial center, which can further reduce the lining's movement away from the axial center. Thus, in the event of wear, the force contact point moves beyond the axial center to the end point (fully worn lining).

[0024] The designs may also be implemented with mirror symmetry at the contact surface.

[0025] The present invention allows for a reduction in lateral forces and a shift in the force contact point on the drum brake lining, which results in reduced lateral forces on the components involved, which do not need to be designed as robustly with respect to these forces.

[0026] This is particularly advantageous for new dry brake systems that apply expansion forces using, for example, a spindle system or a ball / ramp system, since the spindle experiences less lateral force and, in the case of a ball / ramp system, the individual balls are more evenly loaded. The guide system of the expansion unit can also be shortened. This can be used to design components and, therefore, the expansion unit in a smaller size. In the case of dry systems, the lining support is actually also used for force / torque measurement. Here, as mentioned above, it is advantageous to introduce the force centrally in order to increase the accuracy of the force / torque measurement. Furthermore, this also benefits existing hydraulic systems that use guided pistons. In these systems, lateral forces are reduced and possible piston jamming events are prevented.

[0027] The invention may generally improve the application of all drum brake systems (simplex, duplex, dual duplex...) where drum brakes are present.

[0028] In an advantageous embodiment, the smallest possible radius should be selected for Rk, and the largest possible radius (which can even be a straight line) should be selected for Rg. Due to the fact that Rg moves, it must be ensured that the angles 1a°, 1b°, 1'a°, and 1'b° are as small as possible (see Figures 3a / 3b) for Rg when trying to reduce lateral forces as much as possible in the main range of use. This is possible, for example, by offsetting as shown. In the case of Rk, the smallest possible radius is limited by the material properties.

[0029] In principle, the improved support bearings (contact points) according to the invention can be universally provided on different components that are to be mated with each other, i.e., drum brakes / drum brake shoes. Similarly, according to the invention, the improvements according to the invention can also be provided only on very specific drum brake linings, so that, for example, only a preferred rotational direction receives the improvements according to the invention, while other contact points that may be subjected to different load profiles can be configured differently. The contact points can also be configured to a certain extent as mirror images of each other. Furthermore, the "shell-disc design" can also be replaced by a different curvature or an approximate geometric shape instead of a circular shape. Furthermore, the above principle can also be implemented in differential designs in which the lining carrier and the abutment are configured as multiple parts. The present invention may also include the following aspects: 1. A drum brake (1) for a vehicle braking system, in which an actuator means, in particular an electric geared motor drive module with an extender (2) having a gear stage of a rotation-to-translation converter, a transmission means, and / or an actuating element (15, 16) optionally supported on an abutment (3), is in a force flow with movably mounted brake shoes (7, 8) suitable and designed for cooperating with a brake drum (5) via a support bearing, characterized in that a compensating device for lateral offset of the brake shoes is provided adjacent to the extender (2) and / or the abutment (3), and the compensating device is integrated in the force flow of the brake shoes (7, 8) of the drum brake (1) laterally adjacent to the extender (2) and / or the abutment (3). 2. A drum brake (1) for an automobile brake system as described in claim 1, characterized in that the compensation device is arranged in the internal space of the brake drum. 3. A drum brake (1) for an automotive braking system as described in 1. or 2. above, characterized in that the compensation device is integrated so as to fit directly into the interface between the abutment (3) and the brake shoes (7, 8) and / or between the actuating elements (15, 16) and the brake shoes (7, 8). 4. A drum brake (1) for an automotive brake system as described in any one of 1. to 3. above, characterized in that the compensation device is indirectly integrated so as to fit snugly into the interface between the expansion device (2) and the brake shoe (7, 8) and / or abutment (3), in particular by means of at least one adapter component. 5. A drum brake (1) for an automobile braking system as described in any one of 1. to 4. above, characterized in that the compensation device has an articulated or movable bearing arrangement with articulated positive guides in their mutual contact area. 6. A drum brake (1) for an automotive braking system as described in any one of items 1 to 5 above, characterized in that the positive guide of the compensation device between the expansion device (2) / actuating element (15, 16) and the brake shoe (7, 8) and / or abutment (3) is implemented as a track guide having a two-dimensionally curved arcuate shape like a joint disc / joint socket. 7. A drum brake (1) for an automobile brake system described in any one of 1. to 6. above, characterized in that the curved guide configured like a joint has one or more arc segments. 8. A drum brake (1) for an automobile brake system described in any one of 1. to 7. above, characterized in that the paired different arc segments are in close contact with each other with their respective curved surfaces facing in the same direction but having different radii R. 9. A drum brake (1) for an automotive braking system according to any one of the above items 1 to 8, characterized in that the dimensions are determined such that the (major) radius R located on the actuating element side is slightly smaller than the (subordinate) radius R located on the brake shoe side. 10. A drum brake (1) for an automobile brake system described in any one of 1. to 9. above, characterized in that the (major) radius R located on the operating element side is at least approximately 0.6 to 1.5 times the diameter of the brake drum depending on the diameter of the brake drum, and the (minor) radius R located on the paired corresponding brake shoe side is at least approximately 1 / 4 to 1 / 20 times the diameter of the brake drum. 11. A drum brake (1) for an automotive braking system as described in any one of items 1 to 10 above, characterized in that the centers of one or more of the radii R are arranged so as to be offset laterally towards the wheel rotation axis Ax by determined, in particular predetermined, offsets Y1c, Y1d. 12. A drum brake (1) for an automotive braking system as described in any one of items 1 to 11 above, characterized in that all brake shoes (7, 8) are assigned at least one or more compensation devices for lateral offset of the brake shoes with respect to the rotation directions U, U' of all brake drums. 13. A drum brake (1) for an automotive braking system according to any one of claims 1 to 12, characterized in that each brake shoe (7, 8) is assigned a compensation device for the lateral offset of the brake shoe with respect to the direction of rotation U, U' of one brake drum. 14. A drum brake (1) for an automotive braking system as described in any one of items 1 to 13 above, characterized in that the compensation device for the lateral offset of the brake shoes is assigned only to the rotational direction U, U' of one brake drum and only to one or more trailing drum brake shoes (7, 8). 15. A drum brake (1) for an automobile brake system as described in any one of 1. to 14. above, characterized in that the compensation device is fixed to an anchor plate adjacent to the load measuring device and within the brake drum. 16. A drum brake (1) for an automobile brake system described in any one of 1. to 15. above, characterized in that the electric automobile brake system is configured with a control unit (ECU) for open-loop control and / or closed-loop control of the drum brake (1). 17. A drum brake (1) for an automobile brake system described in any one of items 1 to 16 above, characterized in that the electric automobile brake system has at least one or more electromechanically and / or electrohydraulically operable wheel brakes. 18. A drum brake (1) for an automobile brake system as described in claim 17, characterized in that the formed automobile brake system has at least one disc brake. [Explanation of symbols]

[0030] 0 Starting point - New state (reference point) 1 drum brake 2 Expansion Unit 3 Abutment 4 anchor plates 5 Brake drums 6 Brake drum pot 7 Brake shoe (trailing brake shoe when the brake drum main rotation direction is U) 8 Brake shoe (leading brake shoe when the main rotation direction of the brake drum is U) 9 Friction Lining 10 Friction Lining 11 Return spring 12 Return spring 13, 13' Support bearing contact 14, 14' Support bearing contact 15 Actuating Elements 16 Actuating Elements ECU Electrical Control Unit eRB electric wheel brakes EMB Electromechanical Wheel Brakes ehRB electrohydraulic wheel brakes F front side Ax: Wheel rotation axis (axial direction) r radial direction T Tangential direction U Brake drum main rotation direction (preferred rotation direction / main rotation direction) U' Brake drum counter rotation direction x1a, x1b, x2a, x2b offset y1a, y1b, y2a, y2b offsets R radius S Extension axis Q horizontal axis D Drum brake diameter Δx friction lining thickness Z1 Offset end point (worn friction lining) Z2 Offset end point (worn friction lining) Y1c, y1d offset (horizontal offset → projection toward the center)

Claims

1. A drum brake (1) for a motor vehicle braking system, in which a rotation-to-translation converter speed stage or an electric geared motor drive module with an extension device (2) having an actuating element (15, 16) supported on a transmission means is in a force flow with movably mounted brake shoes (7, 8) suitable for and designed to cooperate with a brake drum (5) via a support bearing, comprising a first compensating device for compensating for a lateral offset between the extension device (2) and the brake shoes (7, 8); a first compensating device for compensating for a lateral offset between the brake shoes (7, 8) of the drum brake (1) and a second compensating device for compensating for a lateral offset between the brake shoes (7, 8) are provided adjacent to the extension device (2) and the abutment (3), respectively, the first and second compensating devices are integrated into the force flow of the brake shoes (7, 8) of the drum brake (1) laterally adjacent to the extension device (2) and the abutment (3), respectively, and the first and second compensating devices have a forced-guided articulated or movable bearing arrangement in their contact areas.

2. 2. Drum brake (1) for a motor vehicle braking system according to claim 1, characterized in that the first and second compensating devices are arranged in the interior space of the brake drum.

3. 3. A drum brake (1) for a vehicle braking system according to claim 1 or 2, characterized in that the second and first compensation devices are integrated so as to fit directly into the interfaces between the abutment (3) and the brake shoes (7, 8) and between the actuating elements (15, 16) and the brake shoes (7, 8), respectively.

4. 4. A drum brake (1) for a vehicle brake system according to claim 1, wherein the first and second compensation devices are indirectly fitted into the interfaces between the expansion device (2) and the brake shoes (7, 8) and between the brake shoes (7, 8) and the abutment (3), respectively, by means of at least one adapter component.

5. 5. A drum brake (1) for a vehicle brake system according to claim 1, wherein the forced guides of the first compensation device between the expansion device (2) and the brake shoe (7, 8) and the second compensation device between the abutment (3) and the brake shoe (7, 8) are implemented as track guides having a two-dimensionally curved arcuate shape like a joint disc / joint socket.

6. Drum brake (1) for a vehicle braking system according to claim 5, characterized in that the curved guide configured like a joint has one or more circular arc segments.

7. 7. A drum brake (1) for an automobile braking system according to claim 6, characterized in that the different paired circular arc segments are in close contact with each other with their respective curved surfaces oriented in the same direction but with different radii R.

8. 8. A drum brake (1) for a motor vehicle braking system according to claim 1, characterized in that the (major) radius R located on the actuating element side is dimensioned relative to one another so that it is slightly smaller than the (subordinate) radius R located on the brake shoe side.

9. 9. The drum brake (1) for an automobile brake system according to claim 8, characterized in that the (minor) radius R located on the side of the corresponding paired brake shoe has at least approximately 1 / 5 to 1 / 10 times the diameter of the brake drum.

10. 10. A drum brake (1) for a vehicle braking system according to any one of claims 1 to 9, characterized in that the centres of one or more of the radii R are arranged so as to be offset laterally towards the axis of rotation Ax of the wheel by the determined offsets Y1c, Y1d.

11. 11. Drum brake (1) for a motor vehicle braking system according to any one of claims 1 to 10, characterized in that all brake shoes (7, 8) are assigned at least one or more of the first and second compensation devices for the lateral offset of the brake shoes with respect to the direction of rotation U, U' of all brake drums.

12. 12. Drum brake (1) for a motor vehicle braking system according to any one of claims 1 to 11, characterized in that each brake shoe (7, 8) is assigned the first and second compensation devices for the lateral offset of the brake shoes with respect to the direction of rotation U, U' of one brake drum.

13. 11. A drum brake (1) for a motor vehicle braking system according to claim 1, characterized in that the first and second compensating devices for the lateral offset of the brake shoes are assigned only to one direction of rotation U, U' of the brake drum and only to one or more trailing drum brake shoes (7, 8).

14. A drum brake (1) for a vehicle braking system according to any one of claims 1 to 13, characterized in that the first and second compensation devices are fixed to anchor plates adjacent to a load measuring device and within the brake drum.

15. A drum brake (1) for a vehicle brake system according to any one of claims 1 to 14, characterized in that the vehicle brake system is configured with a control unit (ECU) for open-loop and / or closed-loop control of the drum brake (1).

16. A drum brake (1) for a vehicle braking system according to any one of claims 1 to 15, characterized in that the vehicle braking system has at least one or more electromechanically and / or electrohydraulically actuable wheel brakes.

17. Drum brake (1) for a vehicle braking system according to claim 16, characterized in that the formed vehicle braking system comprises at least one disc brake.

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