Patent Application
20200278002
The invention concerns a brake dust filter for a disc brake assembly with a brake disc and a brake caliper. The brake dust particle filter is configured for catching particles that are produced when braking. The invention concerns moreover a disc brake assembly with such a brake dust particle filter.
It is known to catch and dispose of particles that are produced by brake abrasion by means of a brake dust particle filter. Such particles are produced by friction between brake pad and brake disc of a disc brake. Such a brake dust particle filter has become known, for example, from DE 10 2012 016 835 A1. This brake dust particle filter however requires an integration in a brake caliper housing and is suitable therefore only to a limited extent as a retrofitting solution.
In contrast to this, it is the object of the present invention to provide a brake dust particle filter that is configured to be more efficient for separating particles that are produced when braking as well as suitable for retrofitting of existing vehicles. Object of the present invention is furthermore to provide a disc brake assembly with such a brake dust particle filter.
The brake dust particle filter according to the invention is suitable for any applications of disc brakes, mobile as well as stationary applications. In mobile applications, it can be employed, for example, in passenger cars, trucks, buses rail vehicles. Stationary applications, for example, concern shaft brakes as they are used in wind power devices.
The object is solved by a brake dust particle filter of the aforementioned kind that comprises:
wherein the tongue supports the filter medium and is covered at least at the at least one side surface, in particular completely, with the filter medium.
The object is further solved by a disc brake assembly comprising the brake dust particle filter as claimed.
The dependent claims provide preferred further embodiments.
The brake dust particle filter comprises a ring segment-shaped, approximately banana-shaped and/or helmet-shaped housing. In the housing, the brake disc of a disc brake assembly is received in a mounted state. The housing comprises at least two housing sidewalls and a housing peripheral wall. The housing peripheral wall connects in the mounted state of the brake dust particle filter the two housing sidewalls directly or indirectly. In the interior of the housing, i.e., facing the brake disc, the brake dust particle filter comprises a filter medium. In order to enlarge the effective filter surface of the filter medium, a tongue that supports the filter medium is provided in the brake dust particle filter. According to the invention, the tongue extends at least in sections thereof with at least one radial component away from the housing peripheral wall in a housing interior. The tongue according to the invention has a flat cross-sectional shape and comprises a base surface which is facing the housing peripheral wall, a cover surface projecting into the housing interior as well as at least one side surface. Flat is to be understood herein as a cross-sectional shape whose wide side is much larger than its narrow side. Alternatively, such a cross-sectional shape could also be referred to as flattened or elongate.
The tongue is covered with the filter medium at least partially, namely at least at its side surface, preferably as much as possible, particularly preferred completely. In this way, a higher filtering effect than in the prior art is achieved. The tongue extends in this context preferably from an outer circumference to an inner circumference, i.e., radially inwardly.
In a preferred embodiment, the tongue can have a substantially rectangular cross section wherein a ratio of a wide side to a narrow side of the rectangular cross section is between 15 and 60, preferably between 20 and 40. Such values can be realized for a plurality of sizes of the brake dust particle filter by use of sheet metal plates in standard thicknesses for producing the at least one tongue; for example, sheet metal plates with a thickness (=narrow side of the cross section) between 0.5 and 4 mm can be employed.
In this context, it is not mandatory that the tongue forms a continuous body free of interruptions; instead, it can also be slotted once or multiple times, wherein generally a sufficient support function for the filter medium results even for a slotted tongue. In case of such slotted tongues, the aforementioned ratio specifications refer respectively to an outer contour of the respective tongue and not to the “partial tongues” that are produced by slotting. The tongue can be advantageously made of a mesh material, for example, a metal mesh.
Particularly preferred, the at least one tongue extends in such a way into the interior that its base surface in a mounted state of the brake dust particle filter extends parallel to an axis of rotation of the brake disc.
The tongue can be arranged or embodied at a housing wall, e.g., as one piece together with the housing wall. Preferably, the tongue is arranged or embodied at the housing peripheral wall. Alternatively or additionally, the brake dust particle filter can comprise a filter element, wherein the filter element comprises a filter element support structure on which or at which the filter medium is arranged. In this context, the filter element support structure can comprise the tongue. When providing a filter element, the filter medium is exchangeable particularly easily and environmentally friendly because only the filter element must be exchanged when the filter medium is loaded and not the complete housing. According to this embodiment, a receiving region is advantageously provided for receiving the filter element into which the filter element can be inserted. It can be held, for example, by clips or other fastening elements that appear suitable, in the receiving region. Particularly advantageously, the filter element has a curved shape, in particular a circular arc shape, which corresponds with the inner shape or the radius of the housing peripheral wall.
The filter medium can be fastened indirectly or directly at the tongue, at the housing wall, in particular at the housing peripheral wall, and/or at the filter element support structure. The filter medium can form a fold into which the tongue at least partially extends. In this way, the brake dust particle filter can be produced in a particularly simple way.
According to a further preferred embodiment, at least one additional tongue is provided that projects from at least one housing sidewall into the housing interior. Preferably, the tongue projecting from the housing peripheral wall and the tongue projecting from the housing sidewall form a continuous tongue which comprises an L-shaped or U-shaped basic form. In this way, the effective tongue surface is greatly increased which contributes to an even more improved separation performance. Moreover, in this way a configuration that saves space in radial direction is possible because a portion of the entire tongue surface can be distributed onto the tongue which is provided at the housing sidewall.
The tongue can comprise at least one through opening which is covered by the filter medium. In this way, the filter medium can be flowed through in the region of the tongue. The tongue can advantageously comprise also a plurality of through openings which are each covered by the filter medium.
In a further preferred embodiment of the invention, in the region of the tongue the filter medium is embodied in the form of a collecting pocket or catching pocket for particles wherein the catching pocket is closed in downward direction so that particles cannot fall out of the catching pocket due to the gravity acting on them. The brake dust particle filter can retain in this way large particle quantities. The shape of the collecting or catching pocket can advantageously be imparted to the filter medium by the at least one tongue which has just such a shape. Preferably, a lowest point of the pocket is pointing downwardly in the direction of gravity.
In a further preferred embodiment of the brake dust particle filter, the filter medium comprises at least a first filter layer with a porosity and a second filter layer with a larger porosity. The two filter layers can be embodied in the form of regions (viewed in the direction of thickness) of the filter medium so that the filter medium has a porosity gradient. Alternatively or additionally thereto, an additional filter medium can be provided on the filter medium, wherein the porosity of the additional filter medium differs preferably from the porosity of the filter medium. Due to this arrangement or configuration of different filter layers, the degree of separation of the brake dust particle filter can be matched precisely to the respective application. Advantageously, the pore size in this context decreases in radial direction from the interior to the exterior.
The brake dust particle filter can comprise in addition to the afore described tongue at least one additional tongue in the housing interior. In other words, the brake dust particle filter comprises preferably a plurality of tongues that are projecting inwardly in the housing interior and are preferably arranged spaced apart in circumferential direction. The tongues support the filter medium and are covered at least partially, in particular completely, by the filter medium. By the arrangement or configuration of a plurality of tongues, the filter action is further significantly increased. At least two tongues can be positioned in this context at a different angle relative to the housing peripheral wall, respectively. Angle relative to the housing peripheral wall is understood here as an angle between a tangent, placed at an imaginary contact point of the tongue at the housing peripheral wall, and the length extension of the tongue.
The brake dust particle filter is preferably designed such that the filtering action increases in circumferential direction of the housing. The increase is realized in this context preferably away from a bearing region of the housing, wherein the bearing region is provided for bearing against the brake caliper of the disc brake assembly. In other words, the brake dust particle filter is preferably embodied such that the filter action increases with increasing distance from the brake caliper or from the bearing region for bearing against the brake caliper. A better filter action is understood herein, for example, as the ability of separating finer particle fractions. This is realized in particular by one or a plurality of the following measures:
The brake dust particle filter can comprise at least one opening for the discharge of filtered air in the housing wall, in particular in the housing peripheral wall. Preferably, the brake dust particle filter comprises a plurality of openings for the discharge of filtered air in the housing wall, in particular in the housing peripheral wall.
At least one opening is provided preferably in a housing end region which—viewed in circumferential direction of the housing—is embodied in the region of the brake caliper. The housing end region bridges preferably at least one radially outwardly open region of the brake caliper because, there, a high brake dust discharge occurs typically that, in addition to the brake abrasion that leaves the brake caliper in tangential direction, constitutes the greatest emission source. Preferably, the filter medium is a continuous material strip which extends across the plurality of inwardly positioned tongues as well as across the inner side of the housing peripheral wall in the housing end region.
In order to prevent that air is pressed by the back pressure during driving against the filtration direction through the filter medium, at least one outwardly projecting rib is arranged or embodied at the housing wall, in particular at the housing peripheral wall. Preferably, a plurality of outwardly projecting ribs are provided at the housing wall, in particular at the housing peripheral wall. The at least one outwardly projecting rib can be provided preferably in the region of the at least one opening so that the rib covers the respective opening in the traveling direction at least partially so that a dynamic pressure produced by driving does not act on the opening. Preferably, a plurality of outwardly projecting ribs are provided respectively in the region of an opening for discharge of filtered air, preferably each one of the openings is provided with an afore described rib.
The filter medium is preferably configured such that, even at a temperature of more than 600° C., it is stable in order to withstand the temperatures in immediate environment of a disc brake. In this context, the filter medium can comprise a metal, metal fiber nonwoven, glass, ceramic and/or a high temperature-resistant plastic material, in particular polyether ether ketone. However, the housing should comprise also advantageously a sufficient temperature resistance; for this purpose, it can be embodied of sheet metal, preferably sheet steel. In addition to the excellent temperature resistance, sheet steel has the further advantage that the housing can be obtained by a simple deformation process, for example, by deep drawing.
The ring segment-shaped housing covers preferably a large angle range of the brake disc in order to obtain a high filtration action. The housing extends in this context preferably about a ring segment angle of more than 45°, in particular of more than 75°, particularly preferred of more than 90°. When selecting a suitable enclosing angle, there is a conflict of objectives to be solved between the proportion of particles to be filtered and the cooling performance that can be made available to the disc brake.
For facilitating mounting of the housing, the housing can have a first and a second housing part. The two housing parts preferably can be arranged at least partially axially at both sides of the brake disc. Particularly preferred, the first housing part and the second housing part can be connected in a reversibly detachable way. Alternatively, the two housing parts can also be connected non-detachably, for example, welded. Advantageously, according to this embodiment, the filter medium is inserted already prior to connecting the housing parts so that at least the pre-assembly process is simplified, even though the exchange of the filter medium in service is not. In this case, it is however conceivable to exchange in the service situation the entire brake dust filter (including housing+filter medium) in order to subject it to refurbishing, for example. As an alternative to welding, it can be provided that the first housing part and the second housing part are connected to each other by a crimped connection.
For connecting the two housing parts, a screw connection, a clip connection, a folding mechanism and/or a pivot mechanism can be provided.
The housing peripheral wall can be part of the first housing part or of the second housing part so that it is connected with one of the two housing sidewalls. The housing peripheral wall can be embodied moreover at least partially of housing parts that are overlapping each other.
Particularly preferred, the first housing part comprises the at least one inwardly projecting tongue and the second housing part comprises at least one opening. Further preferred, all inwardly projecting tongues are provided at the first housing part and all openings at the second housing part. The separate configuration of tongue(s) and opening(s) facilitates significantly the production of the brake dust particle filter because the openings, optionally with corresponding ribs, as well as the inwardly positioned tongues can be produced by punching.
A housing part can be pivotable relative to an additional housing part that remains stationary. The pivot axis of such a pivot mechanism can extend parallel to an axis connecting the two housing sidewalls, in particular parallel to the axis of rotation of the brake disc. Particularly preferred, the housing part that comprises the housing peripheral wall is pivotable at least partially relative to the further housing in this case. Alternatively or additionally to this, the pivot axis can extend in the radial direction of the housing or relative to the brake disc, i.e., normal to the axis of rotation of the brake disc. In this case, a first housing sidewall is preferably pivotable relative to the further housing.
The afore described pivoting ability simplifies significantly an exchange of the filter medium in the service situation.
The object according to the invention is furthermore solved by a disc brake assembly with a brake disc, a brake caliper, and a brake dust particle filter as described above.
The brake dust particle filter can have a stationary position relative to the brake caliper, a wheel bearing housing and/or a splash guard. Alternatively or additionally thereto, the brake dust particle filter can be fastened to the brake caliper, to a wheel bearing housing and/or to a splash guard, wherein an attachment at the brake caliper can be advantageously provided when a so-called stationary caliper is concerned. Particularly advantageously, the brake dust particle filter can be connected to the wheel bearing housing at the same fastening points as the brake caliper. Moreover, the screws with which the brake caliper is screwed to the wheel bearing housing can comprise at least in the region of a screw head a blind bore thread so that the brake dust particle filter is connectable with the screws so that advantageously the safety-critical screw connection of the brake caliper (holder) with the wheel bearing housing is not affected (settling/pretension force change).
In a particularly preferred embodiment of the invention, one housing part of the brake dust particle filter can be a splash guard element, in particular splash guard plate, that, positioned inwardly, covers the brake disc at least partially. In this way, an additional splash guard plate is not required so that weight can be saved, which provides driving-dynamic advantages as a result of an arrangement in the unsprung region of a chassis.
In order to effect a particularly effective particle separation, the brake dust particle filter is preferably arranged so as to immediately adjoin the brake caliper. The brake dust particle filter in this context is arranged preferably downstream of the brake caliper, wherein in this context the term “downstream” relates to the rotational direction of the brake disc for an intended forward travel of the vehicle at which the disc brake assembly is provided.
The brake dust particle filter covers preferably at least partially an outer side of the brake caliper, particularly preferred a circumferential outer side of the brake caliper. The coverage of the brake caliper is realized preferably with the housing end region. Particularly preferred, the brake caliper is covered completely in the region of the circumferential outer side, at which often openings for cooling air supply and/or service (removal of the friction pads) are located, at least however in the region of the openings, by the housing end region of the brake dust particle filter so that no unfiltered outflow occurs in this region, but particle-laden air that exits from there first flows through the filter medium and subsequently through the opening in the housing peripheral wall into the environment.
In a further preferred embodiment of the disc brake assembly, the at least one inwardly projecting tongue with its free end is oriented toward the brake caliper. Preferably, a plurality, in particular all, tongues are oriented with their respective free ends toward the brake caliper. In this way, the filter efficiency can be further increased because brake dust particles that are entrained tangentially by the rotation essentially can all be caught by the shape of the tongues.
Further features and advantages of the invention result from the following description of several embodiments of the invention, from the claims as well as the Figures which show invention-relevant details. The features illustrated in the Figures are illustrated such that the particularities of the invention can be made visible clearly. The different features can be realized individually or several thereof combined in any combinations in variants of the invention and are therefore combinable with each other.
The brake dust particle filter 16 comprises a first housing sidewall 17 which forms a part of a ring segment-shaped housing 18. A second housing sidewall 19 (see
The brake dust particle filter 16 can be arranged downstream of the brake caliper 14, in particular in rotation direction R of the brake disc 12 upon forward travel of a vehicle at which the disc brake assembly 10 can be arranged.
In
The housing 18 comprises a housing peripheral wall 26 which extends radially outwardly in circumferential direction of the brake dust particle filter 16. The housing sidewalls 17 (see
The brake dust particle filter 16 comprises moreover tongues 28a, 28b, 28c, 28d. These tongues 28a-28d are arranged at the housing peripheral wall 26 of the brake dust particle filter 16 or embodied as in
A filter medium 32 for cleaning the air from particles is arranged at the tongues 28a-28d and covers the tongues 28a-28d. The filter medium 32 extends across the side of the respective tongue 28a-28d which is facing the housing peripheral wall 26 as well as across the side which is facing away from the housing peripheral wall 26 so that the tongues 28a-28d are covered by the filter medium 32, respectively. The filter medium is a continuous material strip which extends across all tongues 28a-28d as well as across the inner side of the housing peripheral wall 26 in the housing end region 52.
In an exemplary fashion, the facing side is here identified at the tongue 28a by 34 and the side that is facing away by 36. The effective filter surface is thus enlarged by the tongues 28a-28d in circumferential direction of the housing interior 20. The filter medium 32 is moreover arranged at the sections 38a, 38b, 38c of the housing peripheral wall 26 between the tongues 28a-28d. In this way, the filter medium 32 is connected immediately to the housing peripheral wall 26. In particular, it is attached to the housing peripheral wall 26 and/or to the tongues 28a-28d. Alternatively, it can be connected also indirectly to the wall of the housing 18 by means of further intermediate layers. The tongues 28a-28d can comprise one or a plurality of through openings (not shown) which are covered by the filter medium 32.
The tongues 28a-28d form a support structure 40 for the filter medium 32. For this purpose, the tongues 28a-28d project into folds 42a, 42b, 42c, 42d of the filter medium 32.
The filter medium 32 can comprise at least a first region and a second region (not shown). The first region can be embodied between the respective tongues 28a-28d and the second region. In this context, for coarse filtration the first region can comprise a larger porosity than the second region. The filter medium in addition can also comprise a third and/or further such regions of different porosities. As an alternative thereto, the transition from a larger porosity of the filter medium to a smaller porosity in the direction of the tongue 28a-28d can also be continuously realized (gradient).
In a further embodiment, the brake dust particle filter comprises, in addition to the filter medium 32, an additional filter medium (not illustrated). In this context, the filter medium 32 is arranged between the respective tongue 28a-28d and the additional filter medium. The additional filter medium comprises a larger porosity than the first filter medium. In an alternative embodiment, the brake dust particle filter 16 can comprise additional filter media with different porosity.
The brake dust particle filter 16 can be designed such that the filter action on the air moved in the circumferential direction by the brake disc 12 increases. For this purpose, the porosity of the filter medium 32 can decrease in circumferential direction of the housing, beginning at a bearing region 44 of the brake dust particle filter 16 provided for bearing against the brake caliper 14 (see
The brake dust particle filter 16 comprises in its housing peripheral wall 26 openings 46a, 46b (see
Moreover, ribs are arranged and/or embodied outward at the housing peripheral wall 26 at the exterior side 48 and two of them are identified in an exemplary fashion by 50a, 50b. The ribs 50a, 50b are arranged at the openings 46a, 46b so that the air that escapes outwardly is guided by the ribs 50a, 50b in a desired direction. The ribs 50a, 50b prevent a flow through the filter medium from the clean side to the raw side by a dynamic pressure that is generated by the travel speed.
The brake dust particle filter 16 comprises a housing end region 52. The housing end region 52 can comprise at least partially the housing sidewalls 17, 19 and the housing peripheral wall 26. Also, it comprises the filter medium 32 arranged at the housing peripheral wall 26. Outwardly projecting ribs 50a, 50b and openings 46a, 46b in the housing peripheral wall 26 at the ribs 50a, 50b are also arranged and/or embodied in the housing end region 52. The housing peripheral wall 26 extends into the housing end region 52. The housing end region 52 covers in circumferential direction of the brake dust particle filter 16, beginning at the radial outer side of the brake dust particle filter 16, the brake caliper 14, in particular a gap 56 of the brake caliper 14 (see
As illustrated in
As illustrated in
The first housing part 58 and the second housing part 60 can be connected to each other. In particular, they are connectable reversibly to each other in order to be able to perform servicing work quickly. This connection can be realized inter alia by a screw connection of the brake dust particle filter. For this purpose, a housing part 58, 60 can comprise a thread at its outer side and the other housing part 58, 60 a thread at its inner side such that one housing part 58, 60 can be screwed onto the other housing part 58, 60. Alternatively or additionally thereto, the first housing part 58 and the second housing part 60 can be connected by a weld connection, a clip connection, and/or a crimped connection.
As illustrated in
Alternatively or additionally thereto, in a fifth embodiment of the disc brake assembly 10, the pivot axis 66 of the pivot mechanism can extend perpendicular to the outer circumferential side 70 of the housing peripheral wall 26 of the brake dust particle filter 16 in the mounted state, as illustrated in
When reviewing all Figures of the drawing, the invention in summary concerns a brake dust particle filter 16 for a disc brake assembly 10 with a brake disc 12 and a caliper 14. In the housing interior 20 of the housing 18 of the brake dust particle filter 16, at least one tongue 28a-28d is arranged or embodied wherein at least a section of this tongue 28a-28d projects radially inwardly. The tongue 28a-28d forms a support 40 for a filter medium 32 of the brake dust particle filter 16. Moreover, the filter medium 32 covers the surface of the tongue 28a-28d at least partially, in particular completely. The housing 18 has the shape of a ring segment. It can be used to accommodate at least partially the brake disc 12 in the housing interior 20. A first housing sidewall 17 and a second housing sidewall 19 as well as a housing peripheral wall 26, 62, 64 each form parts of the housing 18. The housing sidewalls 17, 19 are spaced apart from each other in axial direction. The housing peripheral wall 26, 62, 64 is arranged radially outwardly in the circumferential direction of the housing 18. The housing peripheral wall 26, 62, 64 is arranged or embodied between the first housing sidewall 17 and the second housing sidewall 19. The brake dust particle filter 16 is configured for catching particles that are produced when braking.
In
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2017 008 421.1 | Sep 2017 | DE | national |
This application is a continuation application of international application No. PCT/EP2018/073600 having an international filing date of 3 Sep. 2018 and designating the United States, the international application claiming a priority date of 8 Sep. 2017 based on prior filed German patent application No. 10 2017 008 421.1, the entire contents of the aforesaid international application and the aforesaid German patent application being incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/EP2018/073600 | Sep 2018 | US |
| Child | 16811252 | US |
