drum brake

Abstract

The invention relates to a drum brake (1), in particular for a commercial vehicle, comprising a brake drum (2) which is rotatably supported about a rotational axis (D), a plurality of brake linings (3) which are supported in a receiving space (22) of the brake drum (2), the brake linings comprising a respective friction lining carrier (32) and a friction lining (31) which is arranged on the friction lining carrier, a pressure device (4) which is arranged on an anchor housing (5) in a non-rotatable manner, the brake linings (3) being pressureable onto an inner circumferential surface (21) of the brake drum (2) which is configured as a friction surface by means of the pressure device, and a cover element (6) which covers an open end side of the brake drum (2) and is supported in a contact-free manner with respect to the brake drum (2), wherein a collecting material (7) for collecting brake dust is arranged on or in the vicinity of an end side edge (23) of the brake drum (2), wherein the collecting material (7) is arranged between the brake drum (2) and the cover element (6).

Description

Technical Field

[0001] The present invention relates to a drum brake as described in the preamble of claim 1. Background Technology

[0002] This type of drum brake has a cylindrical drum-shaped rotor, including friction surfaces disposed on the inner side of the rotor, also known as the brake drum. Braking force is generated here using brake pads, which are pressed against the inner friction surfaces of the brake drum.

[0003] This type of friction brake generates wear material on the brake pads and on the internal friction surfaces of the brake drum. This wear material will escape into the environment in the form of fine particles unless it is sucked out.

[0004] In order to avoid the fine dust load caused by wear of such friction materials, it is desirable to develop a technical solution for friction brakes for commercial vehicles that can minimize brake dust, especially the fine dust portion of brake dust, and ideally prevent the fine dust portion from being emitted into the environment.

[0005] Compared to disc brakes, drum brakes have the advantage that the brake pads are located inside the brake drum, and are therefore easier to seal. Consequently, the largest portion of the main, coarser portion of wear remains within the drum brake and can be removed and recovered from the inside of the brake drum during servicing. This removal is typically carried out using a commercially available vacuum cleaner.

[0006] Because of the relative motion of rotation, gaps will inevitably appear between the moving parts in a drum brake, so through these gaps, particles, especially fine particles, can continue to be discharged from the inside of the brake drum.

[0007] For example, such a drum brake is known from DE102016117778A1. In this drum brake, the open end of the brake drum is covered by a cover. An opening is provided in this cover, and a suction device equipped with a dust removal unit is connected to the opening, which has proven effective in practical use. Summary of the Invention

[0008] The objective of this invention is to provide a drum brake that further improves the ability to prevent brake dust from escaping.

[0009] This task is solved by a drum brake having the features of claim 1.

[0010] In particular, the drum brake according to the invention for commercial vehicles includes: a brake drum rotatably supported about a rotation axis; and a plurality of brake pads supported in the receiving space of the brake drum, the brake pads including a corresponding friction pad carrier and a friction pad disposed on the friction pad carrier.

[0011] A clamping device is provided on the anchor housing of the drum brake in a non-rotatable manner, and the brake pads are clamped to the inner circumferential surface of the brake drum, which is a friction surface, by means of the clamping device.

[0012] The drum brake further includes a covering element that covers at least a portion of the open end side of the brake drum and supports it without contact in the region of the open end side of the brake drum while forming an air gap relative to the brake drum.

[0013] A collection material for collecting brake dust is provided on or near the end edge of the brake drum, wherein the collection material is disposed between the brake drum and the cover element.

[0014] With this type of drum brake, improvements have been made in preventing brake dust from escaping by placing the collection material on or near the end edge of the brake drum, since the brake dust is fixed in the collection material and thus at least largely prevents the brake dust from escaping into the environment.

[0015] The fine dust particles generated during braking, which should not be released for environmental and health reasons, range in size from 2.5 nm to 10 nm. In solid particles of this size, dipole interactions (van der Waals forces) occur when the distance to adjacent surfaces is very small (<100 nm). These holding forces are many times greater than the particle's weight. This invention utilizes this effect to collect braking dust within drum brakes.

[0016] Advantageous embodiments of the invention are the subject of the dependent claims.

[0017] According to an advantageous implementation variation, a recess is formed on or near the end edge of the brake drum, and a collecting material for collecting brake dust is provided in the recess.

[0018] The recess, along with the collection material disposed therein, is covered by a covering element.

[0019] Such a cover is stable, simple and inexpensive to manufacture for harsh environments, and can be easily fastened to the brake drum or anchor housing.

[0020] According to an advantageous implementation variation, the covering element is configured as an annular covering plate.

[0021] According to another preferred embodiment, the covering element has a covering area and a collection area that partially surrounds the collected material, the covering area extending radially from the end edge of the brake drum toward the rotation axis.

[0022] The collection area also serves to deflect the particle flow of brake dust, which is collected in the collection material placed there after entering the collection area of ​​the covering element.

[0023] Furthermore, the kinetic energy of the particles is also suppressed in the collection area.

[0024] According to another preferred embodiment, the covering element has a radially inwardly curved region connected to the collection area, the region being shaped parallel to the outer contour of the brake drum.

[0025] According to a preferred embodiment, the recess for receiving and collecting material is configured as a groove introduced into the end edge of the brake drum.

[0026] This groove can be easily introduced into the end side of the brake drum.

[0027] According to another embodiment, the recess is configured as a material clearance introduced in the transition region between the end edge of the brake drum and the outer peripheral surface of the brake drum. Material is collected in the material clearance, wherein the collected material is received in a space defined by the collection area of ​​the covering element and the contact surface of the brake drum.

[0028] The introduction of this material into the brake drum is also done in a simple way.

[0029] According to another preferred embodiment, the radially inwardly curved region of the covering element extends into the groove-shaped void of the material void in the brake drum. The collecting region and the retaining region are preferably configured as tongues extending radially to the rotation axis of the brake drum.

[0030] Preferably, the annular protrusion extends radially outward from the contact surface of the brake drum. This protrusion primarily serves to guide the flow of air rich in brake dust.

[0031] The covering element is preferably fastened to the anchor housing.

[0032] According to another preferred embodiment, at least one suction connector is provided on the covering element.

[0033] In principle, it is also conceivable to fasten the cover element to the brake drum.

[0034] According to another preferred embodiment, the collected material is fixed, in particular, bonded to the covering element.

[0035] According to another implementation variation, the collected material at least partially, and in particular completely, covers the surface facing the end edge of the brake drum.

[0036] The task is also accomplished by a drum brake, in which, instead of or additionally, a collection material is disposed in a recess covered by a covering element, on or near the end edge of the brake drum, and in the circumferential direction, between adjacent brake pads, a collection material for collecting brake dust is disposed.

[0037] According to an advantageous variant, the collected material is held in retainers fastened to the anchor housing. These retainers are, in an advantageous further configuration, constructed as wire mesh fabric.

[0038] In a preferred embodiment, the collection material is made of one or more of the following materials: metal wool, woven wire mesh, porous metal foam, especially foamed aluminum, or fabric hose filled with particles.

[0039] In the embodiment of the metal wool, the metal wool preferably has a wire thickness between 30 μm and 120 μm when the specific gravity is between 800 g / m² and 1300 g / m².

[0040] Through an advantageous implementation of the geometry of the interface between the brake drum and the cover element, the airflow is transformed into turbulence. Consequently, particles come into contact with the collecting material. When bridging the critical distance with the metal wool or particles already attached to it, a holding force, enormous compared to the particle weight, comes into play, and the particles deposit on the surface of the metal wool or form aggregates with the already attached particles. Here, metal wool is a particularly advantageous material because its metal filaments, especially steel wires, themselves have a very small diameter, as described above. Therefore, the material can provide a very large surface area in a small volume through a multi-layered construction. Attached Figure Description

[0041] The preferred embodiments will be further explained below with reference to the accompanying drawings. Wherein:

[0042] Figure 1 A schematic isometric illustration of one embodiment of the drum brake according to the invention is shown.

[0043] Figure 2 A cross-sectional view is shown of a preferred embodiment of a variant using a drum brake;

[0044] Figure 3 Showing according to Figure 1 An isometric partial enlarged view of the wall of the brake drum of a drum brake, including the covering element and the collecting material disposed thereon;

[0045] Figures 4 to 6 Other alternative implementations of this covering element and the design of the brake drum wall are shown;

[0046] Figure 7 A schematic isometric illustration of another embodiment of the drum brake according to the invention is shown, wherein the brake drum is hidden;

[0047] Figure 8 Show Figure 7 The side view of the drum brake shown is used to illustrate the arrangement of the brake pads and the material collection structure disposed therebetween;

[0048] Figure 9 A cross-sectional view of the area through the wall of the brake drum is shown, including a covering element and a material collection point disposed thereon;

[0049] Figure 10 Showing through Figure 9 A cross-sectional view of the drum brake through the cutting plane indicated by X;

[0050] Figure 11 A side view of the drum brake is shown to illustrate its use. Figure 12 The cutting plane;

[0051] Figure 12 Showing through Figure 11 The cross-sectional view of the cutting plane shown is used to illustrate the collection material disposed between the brake pads;

[0052] Figure 13 This illustrates another embodiment of the drum brake according to the invention, corresponding to... Figure 10 The illustration;

[0053] Figure 14 and Figure 15 Showing according to Figure 13 The drum brake corresponding to Figure 9 and Figure 10 The view;

[0054] Figure 16 Showing according to Figure 13 The drum brake corresponding to Figure 12 Another sectional view;

[0055] Figure 17 A schematic isometric view of the covering element is shown, including a retainer received therein and a retainer for collecting material disposed between the brake pads;

[0056] Figure 18 An equiaxed single illustration shows a retainer, constructed of wire fabric, for collecting material between brake pads; and

[0057] Figure 19 An isometric single illustration is shown for the annular metal wire fabric used to embed on the inside of the covering element. Detailed Implementation

[0058] In the following description of the accompanying drawings, terms such as upper, lower, left, right, front, and rear refer only to exemplary illustrations and positions selected in the respective drawings for drum brakes, brake drums, material collection elements, and covering elements. These terms should not be interpreted restrictively, meaning that these reference relationships may change through different operating positions or mirror-symmetric designs or the like.

[0059] exist Figure 1 In the accompanying drawings, reference numeral 1 generally indicates a preferred embodiment of the invention, a pneumatically or electromechanically driven drum brake, particularly for use in commercial vehicles. The drum brake 1 has a brake drum 2 rotatably supported about a rotation axis D, which is non-rotatably connected to a wheel hub (not shown), preferably a wheel hub of a commercial vehicle, via an anchor housing 5.

[0060] In the space radially inside the outer wall of the brake drum 2, a plurality of brake pads 3 are provided, supported in the receiving space of the brake drum 2. Each brake pad includes a corresponding friction pad carrier 32 and a friction pad 31 disposed on the friction pad carrier. Here, the brake pads 3 are arranged with their friction pads 31 facing the inner circumferential surface 21 of the brake drum 2, as shown... Figure 2 As shown in the example.

[0061] As in Figure 2 As further shown, a clamping device 4 is provided on the anchor housing 5. The clamping device includes a wedge-shaped ring 41 movable on the cylinder liner 51 of the anchor housing 5, parallel to the rotation axis D of the brake drum 2. Using the wedge-shaped ring, the brake pad 3 is radially perpendicular to the rotation axis D of the brake drum 2. Figure 1 The direction r shown can be pressed against the inner circumferential surface 21 of the brake drum 2, which is configured as a friction surface.

[0062] In order to transmit the motion of the wedge ring 41 to the brake pad 3, a corresponding clamping wedge 34, which is part of the corresponding brake pad 3, is provided on the side of the friction pad carrier 32 opposite to the friction pad 31. Here, the clamping wedge 34 is connected to the friction pad carrier 32 via a pressure rod 35.

[0063] Here, the clamping wedge 34 rests against the clamping surface of the wedge ring 41, as in Figure 2 This can be seen from the text.

[0064] Here, the wedge ring 41, for example, is transmitted from the non-braking position along the axis of rotation D of the brake drum 2 by the service brake piston 92. Figure 1 The direction z shown can be moved to the braking position.

[0065] In order to reduce friction between the pressing surface of the wedge ring 41 and the pressing wedge 34 of the brake pad 3, a slider 42 including multiple rolling elements 43 is provided between the wedge ring 41 and the pressing wedge 34 of the brake pad 3.

[0066] In order to implement the radial pressing motion of the brake shoe 3 onto the inner circumferential surface 21 of the brake drum 2, in Figure 2 In the preferred embodiment shown, the clamping device 4 has a brake cylinder arrangement structure 9 that is non-rotatably mounted on the anchor housing 5 within the receiving space 29 of the brake drum 2.

[0067] The brake cylinder arrangement structure 9 has a housing 91 that is fixedly fastened to the anchor housing 5 in the receiving space 29 of the brake drum 2.

[0068] The service brake piston 92 is movably disposed relative to the housing 91, parallel to the rotation axis D of the brake drum 2.

[0069] In addition, the brake cylinder arrangement structure 9 has a parking brake piston 93, which is movable relative to the housing 91 parallel to the rotation axis D of the brake drum 2 and can be loaded by the spring force of the spring element 96 via the intermediate plate 95.

[0070] Here, the spring element 96 is preferably configured as a disc spring, as exemplarily also... Figure 2 As shown in the image.

[0071] The brake cylinder arrangement structure 9 also has a plurality of tappets 94, which are used to transmit the movement of the parking brake piston 93 to the service brake piston 92.

[0072] In addition, a compressed air input section is provided, which is connected to the service brake pressure chamber between the housing 91 and the service brake piston 92 on one hand, and to the parking brake pressure chamber 97 between the housing 91 and the parking brake piston 93 on the other hand.

[0073] Here, the operation of brake shoe 3 is always important for the movement of service brake piston 92, which is achieved by inputting compressed air into the service brake pressure chamber in the case of intentionally reducing the speed of the commercial vehicle, i.e., the so-called service braking process.

[0074] In the case of intentional locking of the brake to prevent unintentional rollover of a commercial vehicle during parking, compressed air present in the parking brake pressure chamber 97 during driving is discharged from the parking brake pressure chamber 97, causing the parking brake piston 93 to move toward the service brake piston 92. This movement is caused by a force applied to the back side of the parking brake piston 93 away from the service brake piston 92 by the spring element 96.

[0075] exist Figure 2 In the illustrated variant, the clamping device 4 is configured such that the brake pad is movable radially toward the inner circumferential surface 21 of the brake drum 2 along the axis of rotation D. However, it is also conceivable that the brake pad is mounted on one or more sub-assemblies that are deflectable toward the inner circumferential surface 21 of the brake drum 2 via a so-called S-cam, as in a so-called simple drum brake. In such a simple drum brake, the clamping device is formed by the S-cam and the sub-assemblies movable via it.

[0076] As in Figure 2 China and in Figures 3 to 6 As shown, at least one portion of the open end side of the brake drum 2 is covered by a covering element 6, which is supported without contact in the region of the open end side of the brake drum 2 while forming an air gap 11.

[0077] A collection material for collecting brake dust is provided on or near the end edge of the brake drum, wherein the collection material is disposed between the brake drum and the cover element.

[0078] exist Figure 2 In the embodiment shown, the covering element 6 also covers the end edge 23 of the brake drum 2 or a recess formed near the end edge, in which a collecting material 7 for collecting brake dust is provided.

[0079] Here, the covering element 6 is preferably configured as an annular covering plate.

[0080] The air gap 11 is also preferably formed annularly, and as exemplarily in Figures 3 to 6 As shown, it extends between the end edge of the brake drum 2 and the inner surface of the cover element 6 facing that end edge.

[0081] exist Figure 3 In the embodiment shown, the cover plate has a covering area 61 that extends in a portion of the end edge 23 of the brake drum 2 and in a region radially within the inner circumferential surface 21 of the brake drum 2. The covering area extends radially from the end edge 23 of the brake drum 2 toward the rotation axis D, and the cover plate has a collection area 62 that partially surrounds the collection material 7.

[0082] The collection area 62 extends into a recess 24 formed in the end edge 23 of the brake drum 2, where the collection material 7 is received.

[0083] like Figure 1 and Figure 2 As further shown, the covering element 6 is preferably fastened to the anchor housing 5 using screws.

[0084] It is also conceivable that the covering element 6 is fixed on the brake drum 2, especially in the area of ​​the outer peripheral surface of the brake drum 2.

[0085] The brake shoes are movably positioned in the gap between the anchor housing 5 and the inner circumferential surface 21 of the brake drum 2 by the covering element 6 covering the gap, so that the brake dust generated during braking will not escape from the inside of the brake drum 2 into the wheel cover of the vehicle wheel, but will be mostly sucked out directly from the internal space of the brake drum 2 by the suction device.

[0086] Therefore, in the embodiment shown here, a suction connector 8 is provided on the covering element 6, the suction connector including a suction tube 81 and a retaining lip 82, and a connecting hose (not shown) of the suction device can be inserted into the retaining lip.

[0087] Another portion of the brake dust reaches the collection area 62 of the cover element 6 through the remaining gap between the cover area 61 of the cover element 6 and the end edge 23 of the brake drum 2, as the airflow is guided through the underside of the cover element 6 toward the end edge 23 of the brake drum 2.

[0088] By using the collection material 7 provided in the collection area 62, brake dust arriving in the area can be collected in the collection material 7, and in maintenance situations, the collection material 7 filled with brake dust can be replaced.

[0089] Here, the collected material 7 can be formed into a filter pad, and is preferably made of metal wool, woven metal wire mesh or porous metal foam, especially foamed aluminum.

[0090] Alternatively, the collection material could be constructed using a structure of a fabric hose filled with granules.

[0091] The collected material 7 is preferably held, or preferably clamped, onto the covering element 6 by the shaping of the collecting region 62. Here, the collecting region 62 is preferably configured in a small size as a continuation of the bend of the covering region 61.

[0092] Alternatively, it is conceivable to additionally bond the collected material 7 to the covering element 6.

[0093] exist Figures 4 to 6In the embodiment shown, the recess on the brake drum 2 is configured as a material void 25 introduced in the transition region between the end edge 23 and the outer peripheral surface 22 of the brake drum 2, in which the collecting material 7 is received.

[0094] Here, the collected material 7 is received in the space defined by the collection area 62 of the covering element 6 and the contact surface 26 of the brake drum 2.

[0095] Here, the collection area 62 is preferably configured as a bag in cross-section, so that the collection material 7 is received in the bag-shaped portion, and preferably fixed on the inner surface of the bag-shaped portion. Here, the air gap 11 preferably extends between the collection material 7 and the contact surface 26 of the brake drum 2.

[0096] In addition, Figures 4 to 6 In the embodiment shown, the covering element 6 has a radially inwardly curved region 63 connected to the collection region 62, which extends toward a groove-shaped opening 27 in the region of the material opening 25 of the brake drum 2, thereby enabling further vortexing of the airflow from the air gap 11 through the collection region 62.

[0097] For example, further Figure 5 and Figure 6 As shown, in order to actively influence the airflow rich in brake dust, an annular protrusion 28 extends radially outward from the contact surface 26 of the brake drum 2.

[0098] exist Figure 5 In the embodiment shown, the protrusion 28 is formed close to the groove-shaped empty portion 27.

[0099] exist Figure 6 In the embodiment shown, the protrusion 28 extends directly radially outward as an extension of the end edge 23 of the brake drum 2.

[0100] In all the illustrated implementation variations, the collecting material 7 is configured in such a way that it occupies as completely as possible the space between the inner side of the collecting area 62 and the corresponding contact surface 26 in the area of ​​the groove 24 or material clearance 25 of the brake drum 2.

[0101] Overall, the covering element 6, including the collection material 7 disposed thereon, should be installed on the brake drum 2 in a simple manner and can be installed on the brake drum 2 quickly and easily.

[0102] Using this covering element 6, which includes the collection material 7 disposed thereon, particularly helps to reduce the environmental impact caused by brake dust and extend the service life of drum brakes.

[0103] In principle, it is also conceivable that the cover element is arranged on the brake drum without any gaps in the area of ​​the end edge 23 of the brake drum 2, wherein the collecting material 7 is received, for example, between the brake drum 2 and the area where the cover element 6 is rolled or bent toward the brake drum 2.

[0104] exist Figures 7 to 19 Other embodiments of the drum brake according to the invention are shown in the figure.

[0105] As in Figure 7 , 8 As shown in 12, 13, 16 and 17, in these implementation variations, when viewed circumferentially from the brake drum, a collection material 7 for collecting brake dust is also provided between adjacent brake pads 3.

[0106] The arrangement of the collecting material 7 between adjacent brake pads 3 constitutes a further significant improvement in collecting brake dust generated during braking, because brake dust particles are thrown off tangentially in the direction of rotation of the brake drum 2 when the friction material is pressed against the friction surface of the brake drum 2.

[0107] Brake dust particles are not directly emitted into the environment, but are first thrown into the space between the anchor housing 5, the brake drum 2 and the cover element 6.

[0108] Based on the available space between adjacent brake pads, a correspondingly large area is set for collecting material 7.

[0109] The collection material 7 disposed between adjacent brake pads 3 is preferably held on a retainer 14, which is itself fixed to the anchor housing 5.

[0110] As in Figure 8 and 12 As can be further seen, the retainer 14 here includes a tab, through which a bolt extends parallel to the rotation axis of the brake drum 2, and the bolt is guided through the collection material 7.

[0111] The radial thickness of the collection material 7 disposed in the area between the brake pads 3 is determined in such a way that the collection material is used to maximize the use of the space between the brake pads 3, the anchor housing 5 and the brake drum 2.

[0112] For example, further Figure 9 and Figure 10 As shown in the embodiment variant illustrated here, the collecting material 7 disposed below the covering element 6 is used not only in the region of the groove-shaped empty portion of the material empty portion 25 of the brake drum 2, but also in the entire U-shaped cross-section of the covering element 6, wherein the axial thickness of the collecting material 7 varies depending on the available space.

[0113] Therefore, especially in the area not occupied by the brake pad 3, a larger axial thickness is formed, such as in Figure 10 As shown in the image.

[0114] The material 7 is disposed at least partially on the surface facing the end edge 23 of the brake drum 2, or in the illustrated embodiment, completely covering the surface facing the end edge 23 of the brake drum 2.

[0115] exist Figures 13 to 19 In the implementation variant shown, the implementation variant substantially corresponds to Figures 7 to 12 In the illustrated implementation variation, the collecting material 7 is secured by retainers 12, 13, and 14, which are at least partially constructed of wire fabric, as shown in... Figures 17 to 19 As shown in the image.

[0116] If the collecting material 7 is made of metal wool, it preferably has a wire thickness between 30 μm and 120 μm when the specific gravity of the collecting material is between 800 g / m² and 1300 g / m².

[0117] The steel wool material used as the collection material 7 is particularly advantageous here because the steel wool wires provide a very large surface area in a small volume due to their very small diameter.

[0118] In addition, steel wool is very heat-resistant and its wear is similar to that of other materials, since brake drum 2 itself is also made of a material containing iron.

[0119] List of reference numerals

[0120] 1. Drum brake

[0121] 2 Brake Drums

[0122] 21 inner circumferential surface

[0123] 22 outer perimeter

[0124] 23 Edge

[0125] 24 slots

[0126] 25 Material gaps

[0127] 26 backrests

[0128] 27. Leave blank space

[0129] 28 protrusions

[0130] 29 Acceptance Space

[0131] 3 brake shoes

[0132] 31 Friction Liner

[0133] 32 Friction Liner Carrier

[0134] 33 friction surfaces

[0135] 34 clamping wedges

[0136] 35 pressure tappet

[0137] 4. Pressing equipment

[0138] 41 wedge ring

[0139] 42 sliders

[0140] 43 Rolling bodies

[0141] 5 Anchor-type shell

[0142] 51 cylinder liner

[0143] 6 Covering elements

[0144] 61 Covered Area

[0145] 62 Collection Area

[0146] Area 63

[0147] 7. Collect materials

[0148] 8 suction connector

[0149] 81 suction tube

[0150] 82 Keep your lips

[0151] 9-cylinder arrangement structure

[0152] 91 casing

[0153] 92 service brake piston

[0154] 93 parking brake piston

[0155] 94 paddles

[0156] 95 intermediate board

[0157] 96 Spring Components

[0158] 97 Parking Brake Pressure Chamber

[0159] 10. Brake dust collection device

[0160] 11 air gaps

[0161] 12 retainers

[0162] 13 retaining parts

[0163] 14 retainers

[0164] D Rotation axis

[0165] R and z directions

Claims

1. Drum brakes (1), especially for commercial vehicles, including: - A brake drum (2) that is rotatable about the axis of rotation (D). - A plurality of brake pads (3) supported in the receiving space (22) of the brake drum (2), the brake pads including corresponding friction pad carriers (32) and friction pads (31) disposed on the friction pad carriers. - A clamping device (4) is non-rotatably mounted on the anchor housing (5), and the brake pads (3) can be clamped to the inner circumferential surface (21) of the brake drum (2), which is configured as a friction surface, by means of the clamping device. - A covering element (6) that covers at least a portion of the open end side of the brake drum (2) and is supported without contact in the region of the open end side of the brake drum (2) while forming an air gap (11) relative to the brake drum (2). Its features are, - A collection material (7) for collecting brake dust is provided on or near the end edge (23) of the brake drum (2). -The collecting material (7) is disposed between the brake drum (2) and the covering element (6).

2. The drum brake (1) according to claim 1, characterized in that, A recess is formed on or near the end edge (23) of the brake drum (2), and a collection material (7) for collecting brake dust is disposed in the recess, wherein the recess and the collection material (7) disposed in the recess are covered by the covering element (6).

3. The drum brake (1) according to claim 1 or 2, characterized in that, The covering element (6) is configured as an annular covering plate.

4. The drum brake (1) according to any one of the preceding claims, characterized in that, The covering element (6) has a covering area (61) and a collection area (62) that partially surrounds the collection material (7), the covering area extending radially from the end edge (23) of the brake drum (2) toward the rotation axis (D).

5. The drum brake (1) according to claim 4, characterized in that, The covering element (6) has a radially inwardly curved region (63) connected to the collection area (62), the region being shaped parallel to the outer contour of the brake drum (2).

6. The drum brake (1) according to any one of claims 2 to 5, characterized in that, The recess is configured as a groove (24) introduced in the end edge (23) of the brake drum (2), in which the collection material (7) is received.

7. The drum brake (1) according to any one of claims 2 to 5, characterized in that, The recess is configured as a material void (25) introduced in the transition region between the end edge (23) and the outer peripheral surface (22) of the brake drum (2), in which the collecting material (7) is received, wherein the collecting material (7) is received in the space defined by the collecting area (62) of the covering element (6) and the contact surface (26) of the brake drum (2).

8. The drum brake (1) according to any one of claims 5 to 7, characterized in that, The radially inwardly curved region (63) of the covering element (6) extends into the groove-shaped cavity (27) of the material cavity (25) of the brake drum (2).

9. The drum brake (1) according to claim 7 or 8, characterized in that, An annular protrusion (28) extends radially outward from the contact surface (26) of the brake drum (2).

10. The drum brake (1) according to any one of the preceding claims, characterized in that, The covering element (6) is fastened to the anchor housing (5).

11. The drum brake (1) according to any one of the preceding claims, characterized in that, At least one suction connector (8) is provided on the covering element (6).

12. The drum brake (1) according to any one of the preceding claims, characterized in that, The covering element (6) is fastened to the brake drum (2).

13. The drum brake (1) according to any one of the preceding claims, characterized in that, The collection material (7) is fixed, in particular, adhered to the covering element (6).

14. The drum brake (1) according to any one of the preceding claims, characterized in that, The collected material (7) at least partially, and especially completely, covers the surface facing the end edge (23) of the brake drum (2).

15. The drum brake (1) according to any one of the preceding claims or the preamble of claim 1, characterized in that, Looking in the circumferential direction, a collection material (7) for collecting brake dust is provided between adjacent brake pads (3).

16. The drum brake (1) according to any one of the preceding claims, characterized in that, The collected material (7) is held in retainers (12, 13, 14) fastened to the anchor housing (5).

17. The drum brake (1) according to claim 16, characterized in that, The retaining members (12, 13, 14) are at least partially composed of metal wire fabric.

18. The drum brake (1) according to any one of the preceding claims, characterized in that, The collection material (7) consists of one or more of the following materials: metal wool, metal wire mesh, porous metal foam, especially foamed aluminum, and fabric hose filled with particles.

19. The drum brake (1) according to claim 18, characterized in that, The metal wool has a wire thickness between 30 μm and 120 μm at a specific gravity between 800 g / m² and 1300 g / m².

Images