Patent Grant
11655865
The present invention relates to devices for separating contaminants generated during braking, typically through the action of pads against a rotor disk rotating about an axis. The field of application of the invention relates in particular to the separation of dust and water in order to render a brake assembly non-polluting during the braking of a road vehicle (for example an automobile, a heavy goods vehicle, a motorbike) or a rail vehicle (a train, a tram, an underground train).
As is known per se, there is a need to process the dust and particles that result from abrasion in friction braking systems. The dust and particles may first of all be captured by aspiration, as described for example in document DE 42 40 873 C2 or in document FR 3 046 644 and the flow is then filtered against a filter membrane/wall. It is also known practice, according to document DE 20 2008 009 717 U1, to collect and hold the dust and particles in the filter media, for example which has a U-shaped cross section, which filter media is mounted as close as possible to the caliper support.
Document DE 10 2017 201736 describes the installation of a simple cyclone to separate brake particles. However, the separation effectiveness remains limited.
In practice, systems involving filter media are not particularly effective in the long term. When the filter media is situated too close to the braking zone, the temperatures may reach around 600° C., which limits the choice of filter media and reduces the pollutant-reduction performance.
In addition, the dust and particles captured often form a disparate mixture, particularly when there is also water present. Liquid saturation of the filter membrane encourages premature clogging for example.
There is therefore a need for reliable and robust solutions which offer a good compromise between effectiveness and suitability for the complexity of the types of dust and particles that are to be separated, throughout the life of the separation device.
It is also desirable to limit the risk of clogging or pressure drop when the flow of air that is to be purified is laden with water.
It is an object of the present invention to alleviate one or more of the aforementioned disadvantages by proposing a more effective separation device for suitably separating the pollutants resulting from a mixture collected in the braking zone. To that end, the invention relates to a device for separating brake dust and particles, for collecting dust and particles produced by one or more pads of a brake assembly, the device comprising:
Typically, the group of cyclones forms a transverse barrier connected in a fluidtight manner to the axial duct, the transverse barrier and the axial duct preventing a heterogeneous liquid-solid mixture from traveling back up toward the downstream zone during operation of the device. As a preference, only the gravity discharge orifices are able to fill the trapping zone with a heterogeneous liquid-solid mixture during operation of the device. Thus, in the event of a jolt during a phase in which the vehicle is running, contamination of the downstream zone is avoided.
Advantageously, the inlet to the device is formed at the bottom of the casing and the axial duct causes the flow to circulate, preferably linearly, as far as a zone of connection of the intake manifold. With this type of arrangement, it is possible to form a device that is compact in terms of width, having a small cross section of casing by splitting the flow into as many flows as there are cyclone cells (these cells being mounted in parallel). Furthermore, when a filtration stage, centralized or provided in the casing (downstream of the centrifugal separation means), is incorporated, the device is able very effectively to process all of the brake dust and, in particular, the metallic particles on the one hand, and the dust and fine particles of variable size on the other hand, even when there is water present.
The separation or preseparation permitted by the group of cyclones can thus be effective, by making it easier for all the heavy dust or particles to fall under the effect of gravity, making it possible to improve the life of a filtration stage situated downstream of these separation means. In all that follows, the heavy dust or particles should be understood as meaning dust or particles of relatively large size which therefore drop quickly under the effect of gravity. Recourse to branches for tangentially guiding the flow around each substantially vertical axis of the cyclones provides the possibility of exerting a centrifugal force which contributes to increasing, by agglomeration, the size of the dust pushed toward the outside on the one hand, and serves to make it easier for this dust to drop under gravity via the gravity discharge orifice, on the other hand.
According to one particular feature, the group of cyclones forms a structural unit that can be inserted as a single piece into the interior volume of the casing.
As a preference, the group of cyclones forms a multi-cyclone structural unit that can be fitted in a fluidtight and centered manner onto the axial duct formed as an internal axial projection in a bowl belonging to the casing.
The intake manifold allows the flow to be distributed symmetrically. The separation device can therefore limit the length of the circulation path followed by the flow that is to be processed in the group of cyclones, while at the same time having good effectiveness, in the knowledge that the flow is distributed radially (via a first deviation effect which immediately precedes the cyclone effect) to a high number of cyclones, for example around ten cyclones.
The inlet of the device is preferably produced as an axial end of the axial duct, which is typically a cylindrical duct.
According to one particular feature, the exhaust shafts/stacks project upward with respect to a flange of the group allowing for mounting in the casing.
According to one option, the exhaust stacks project upward with respect to a flange of the group delimiting a top of the intake manifold, the exhaust stacks having convergent outlet orientations so as to move the air leaving the cyclones away from a lateral wall of the casing.
In embodiment options for the device according to the invention, recourse may also be had to one or more of the following arrangements:
According to one particular feature, each of the exhaust stacks has:
Typically, the deceleration members are oriented in the opposite direction with respect to an end wall of the casing, for example facing an inlet face of a filter media of a filtering element placed in the casing in the downstream zone.
Optionally, the filtering element is axially spaced/distant from an axial outlet of the casing, so as to delimit a clean zone in the hollow of a lid of the casing.
According to one option, the separator device may optionally further comprise a coalescing means arranged internally inside a tubular element connected by an elbow to the axial duct from beneath so as to separate out liquid before it enters the axial duct and/or before it enters the cyclones. Typically, the tubular element with coalescer extends horizontally, while the axial duct extends vertically (just like the bodies of the cyclones which are vertically elongate).
Also proposed is an air separation unit to be mounted in series with/downstream of a brake dust collecting line, the separation unit comprising the brake dust and particles separation device according to the invention and further comprising at least one filtering element provided with a filter media, in the knowledge that the filtering element is incorporated internally inside the casing that houses the group of cyclones or else is placed in an independent casing downstream of the outlet of the casing.
Typically, each filtering element of the separation unit extends in the downstream zone inside the casing, delimiting:
That yields an arrangement that is compact combining a number of separation functions in a brake dust recovery circuit during the phases in which a vehicle equipped with the device is running.
According to one particular feature, the filtering element has passing through it a flow of air which circulates parallel to the longitudinal axis through the filter media.
According to another particular feature, the filtering element has the shape of an annulus around a hollow interior space through which there passes a flow of air which circulates centripetally from a peripheral annular region included in the intermediate zone as far as the hollow interior space included within the clean zone.
According to one option, the separation means and an end wall of the casing delimit axially between them the trapping zone, which is in the form of an annular lower compartment of the casing.
As a preference, the at least one filtering element constitutes a trap for solid particles that are finer than the dust and particles stored in the trapping zone, the filtering element extending in an upper compartment of the casing, blocked axially against a casing component engagement edge and an annular end of the lid. The engagement edge may optionally consist of an internal annular shoulder of the casing component.
According to one option, the group of cyclones extends internally in a bowl of the casing, while the filtering element extends entirely above the bowl, the outlet of the casing being positioned axially or radially in a removable top lid of the casing, the top lid preferably being removable from the bowl which constitutes a stationary part connected directly to the vehicle.
With such an arrangement it is possible easily to fit and remove the filtering element, independently of the group of cyclones, possibly without a special-purpose tool. In a preferred option, clips or a screw thread may be provided for attaching the lid. In one option, the filter is designed as a non-removable unit and the filter assembly is changed during maintenance operations.
Typically, the filter media is pleated, forming fold lines which are either perpendicular to the longitudinal axis or parallel to the longitudinal axis.
Optionally, the support structure supporting the filtering element forms a poka-yoke/foolproof means designed and arranged so that it is not possible to keep the lid closed (in a locked state) without the filtering element, there then being nothing to oppose a removal of the lid.
In one option, the first fixing members are inaccessible from outside the casing and comprise or consist of elastically deformable clip-fastening members able to disengage from the casing component in a modified orientation of the support structure.
The casing may optionally contain, in the clean zone, a turbine rotor able to aspirate the flow of air admitted via the inlet of the casing.
According to one particular feature, deflector means formed between the exhaust stacks and an inlet face of the filter media are provided. Optionally, the deflector means comprise:
The deflector means may potentially be supported by or extend parallel to a transverse wall parallel to an upper flange of the group of cyclones, the transverse wall.
Each of the deflector means may be of the type having a concave face facing a deceleration member of the exhaust stacks (a flared member projecting axially upward from an upper flange of the cyclone separation means).
According to one option, the separated particles are trapped in the casing and collected in a trapping zone of which the height, measured from the cyclones, is greater than the height of the body of the cyclones measured between the upper flange and the annular end forming the gravity discharge opening. Typically, the height of the trapping zone beneath the cyclones is less than the height of the downstream zone Z2 delimited by the casing, bearing in mind the volume occupied by the filtering element or elements.
More generally, it is advantageously possible to obtain a non-polluting brake assembly comprising:
According to one option, the collector device has aspiration/suction means arranged at least in part in the vicinity of the caliper support, so that each inlet of the collector device is defined by an aspiration zone formed in the vicinity of each pad and delimited by a deflector.
According to another aspect, it is proposed a use of the separation device according to the invention in a vehicle or mobile plant that generates brake dust and particles, having the particular feature that the inlet formed by the casing defines a cannula to which a connecting element, preferably a flexible hose, is fixed, for the purposes of connection to a brake dust collector device, the casing being attached by fixing means to a strut of a suspension damper.
According to another aspect, it is proposed the use of the separation device according to the invention in a vehicle or mobile plant that generates brake dust and particles, having the particular feature that the trapping zone is formed by a lower stage of the separation device and serves to hold the brake dust and particles as well as liquid droplets which have been separated by the group of cyclones around an axial duct carrying a raw air flow upward directly into the intake manifold.
The separation of the solid dust/particles and of the water that the group of cyclones of the device permits may be a relatively coarse separation notably targeting the heaviest dust or particles, allowing subsequent use of a filtration stage the media or medias of which will become saturated less quickly (as water is not a compressible fluid and the large-sized dust is held in the trapping zone).
Further features and advantages of the invention will become apparent during the following description of a number of embodiments, given solely by way of nonlimiting example, with reference to the attached drawings in which:
There follows a detailed description of a number of embodiments of the invention, accompanied by examples and with reference to the drawings. In the various figures, identical references indicate elements that are identical or similar.
Referring to
As is clearly visible in
An inlet E formed by the casing 2 may define a cannula C3 onto which a connecting element 13, in this instance a flexible hose, is fixed to connect to the collector device 100. The hose optionally is duplicated by two branches 13a, 13b so as to be able to collect the dust coming from the friction zones associated with the two pads 72a, 72b respectively.
The casing 2 may be secured to a component installed in the bottom part of the vehicle or mobile plant equipped with the brake assembly 7. In the example illustrated, the casing 2 is attached, by virtue of fixing means 92 (possibly resorting to screws/bolts), to a strut 91 of a suspension damper 90.
As illustrated in the view in longitudinal section of
The casing 2 of the device 1 may have a shape that is substantially tubular about a longitudinal axis A, which may be a substantially vertical central axis. In the nonlimiting example of the figures, the end wall 3 of the casing 2 is defined by or forms part of a bowl 2a, typically made of metal or of plastic, visible in
With reference to
In embodiment options, the lid 2c may have a flattened shape rather than a domed shape. Furthermore, the outlet 8 may correspond to an opening which may directly form an interior passage of a turbine. By way of example, the bowl 2a or similar casing component may be closed by an electric turbine 32, 33, 34.
In
With or without the presence of a turbine, the presence of at least one filtering element 20 is preferred so as to define a clean zone Z3 internal to the casing 2. The example of
In any event, a main separation of particles and dust from an incoming flow F is provided by separation means 5 of the cyclone type, such separation means 5 delimiting within the casing 2 an upstream zone Z1 in communication with the inlet E of the device 1, and a downstream zone Z2 in which a purified flow intended for the outlet 8 can circulate.
Thus, with reference to
In this instance, the trapping zone Z4 is delimited by the end wall 3 and the bottom of the lateral wall P2, extending below the separation means 5. The downstream zone Z2 delimited by the separation means 5 extends entirely above the separation means 5 in the casing, axially opposite the inlet E. If one or more filtering elements 20 is or are present in the downstream zone Z2, it will be appreciated that the clean zone Z3 in which the filtered air circulates constitutes a (typically upper) sub-zone of the downstream zone Z2.
The separation means 5 which subdivide the incoming flow F and which use a centrifugal effect to recover the most dense particles in the trapping zone Z4 will now be described in greater detail.
Referring to
Each of the cyclones 6 comprises a body 15 that tapers in the downward direction having a lower end 16 opening via a gravity discharge orifice O6 into the trapping zone Z4 delimited by a lower compartment C1 of the casing 2. The bodies 15 are grouped together in an annulus around the longitudinal axis A and around the supply inlet 10 common to all the cyclones 6 of the group. An intake manifold 11 is provided to distribute the flow F to the various cyclones 6 of which in the nonlimiting example of the drawings there are ten, this number typically being greater than six. The supply inlet 10 has a tubular connector 10a for connecting the intake manifold 11 to the duct 4 including the inlet E, by fitting these together axially. In one preferred embodiment, the duct 4 and the bowl 2a that forms the end wall 3 of the casing 2 may be produced as a single piece.
Stiffening walls P which connect pairs of adjacent bodies 15 in the group may be able to form a tubular internal partition running concentrically around the axial duct 4 that defines the inlet E. This non-perforated partition extends as far as an annular lower end E6 of the group of cyclones 6. The axial duct 4 fits together with the tubular connector 10a (in this instance a central connector) of the supply inlet 10 and in a fluidtight manner separates a downstream zone Z1 corresponding to the inside of the tube that forms this duct 4 and the trapping zone Z4 formed beneath the group of cyclones 6.
The formation of a continuous tubular internal partition, by the cyclones 6 and the stiffening walls P, may make it possible to prevent the heterogeneous mixture collected in the bottom of the compartment C1 from being splashed (if there is a jolt during the running of the vehicle on board which the device 1 is carried) toward annular seals contributing to the sealing of the connection between the group of cyclones 6 and the lateral wall P2 of the casing 2. A risk of premature aging of the seals may thus be avoided and/or this offers a greater range of choice of the seal to be used. It will be appreciated that this design is advantageous for obtaining a shielding effect that prevents raw substance from flowing back up, the walls P here being formed integrally with the bodies 15 of the cyclones 6.
Annular sealing contact is also achieved between a cylindrical bearing surface F10 of the connector 10a and an annular seal J fitted to an upper end of the axial duct 4, for example in a groove provided for that purpose. In this example, the axial duct 4 forms a male member that fits into a connector of female type formed integrally with the intake manifold 11, typically in an axial continuation of a branching zone of the intake manifold 11. In a variant, the axial duct 4 may also form a female member engaging in a tubular connector 10a of male type, formed integrally with the intake manifold 11, typically in an axial extension of the branching zone.
The separation means 5 formed by the cyclones 6, the common flange 16 and the manifold 11 may be produced in two or three parts each molded in a plastics material. For example, the flange 16 which includes the central part 17 belonging to the manifold 11 may be produced as a single piece. Optionally, all or some of the exhaust shafts/stacks 50 are also formed as one with the flange 16.
As can be seen in
In
Here, an upper flange 16 is optionally provided to allow the group of cyclones 6 to be mounted on a receiving rim or edge B2 of the casing 2. The upper flange 16, which may be produced as a single piece, is provided with passages for the air ascending in the respective exhaust stacks 50 of the cyclones 6. The upper flange 16 may also form the crown 16a of an arch in a central part 17 surrounded by the exhaust stacks 50, so as to form a respective top of each of the branches 12 and a top of the branching zone (zone of divergence) of the intake manifold 11. The central part 17 forms the arch arcs. The central part 17 forms the top of the intake manifold 11. The profile of the respective branches 12 here is substantially a quarter of an annulus, so far as their profile viewed in longitudinal section of the device 1 is concerned. The arched lower part of the branches 12 is formed substantially at the same heightwise level as the crown 16a of the arch and axially joins the connector 10a of cylindrical shape.
The branching zone is, for example, central so as to distribute the flow centrifugally, in at least six distinct directions, for example ten distinct directions in the case of the drawings illustrated. The intake manifold 11 may therefore form a corresponding number of inlets 22 to deliver a tangential flow, centrifugally.
Each exhaust stack 50 of a cyclone 6 includes a tubular insert 50a projecting axially downward with respect to the upper flange 16, of which at least a portion faces a radial mouth 12b of one of the branches 12 of the intake manifold 11. The radial mouth 12b is offset to one side with respect to the central axis of the tubular insert 50a, as is clearly visible in
In
In the nonlimiting example of the figures, the upper flange 16 provides fluidtight separation by delimiting the downstream zone Z2 with respect to the trapping zone Z4. In addition, the intake manifold 11 and the tubular wall of the axial duct 4 provide fluidtight separation of the upstream zone Z with respect to the trapping zone Z4. Only flows which have passed in succession through:
It may be noted that the device 1 is able to limit the length of the circulation path of the flow to be processed while at the same time having good effectiveness in the knowledge that the flow is distributed radially, centrifugally by a first deflection effect, toward a high number of cyclones 6, for example ten cyclones 6.
A flange B of the bowl 2a forms, for example, the receiving edge B2. An annular border 16b of the flange 16 may, in one option, be trapped/sandwiched between two flat seals JP1, JP2 (visible in
The exhaust stacks 50 may have a profile allowing the removal, with a deceleration effect, of the air which escapes naturally via the top of the separation chambers 18. For example, each of the exhaust stacks 50 extends as an axial projection on each side of the upper flange 16, forming a tubular deceleration member T, having a flared shape that widens in the direction of the outlet 8. The deceleration member T protrudes beyond the top of the substantially planar annular radial portion 16r of the upper flange 16 and is able to deflect the flow of air leaving a separation chamber 18 by being bent slightly inward, for example extending about an axis X which deviates from the vertical by 20 to 50°, as visible notably in
In embodiments that employ a filtering element 20 housed in the interior volume of the casing 2, the respective axes X defined by the deceleration members T intersect at a central point of intersection contained within the interior volume of the casing 2. It is preferable for the cyclones 6 to be symmetrical about the longitudinal axis A when the axial duct 4 is a central duct of the casing 2.
Ways of incorporating one or more filtering elements 20, typically into the interior volume of the casing 2, are described in greater detail in what follows.
In the case of
Annular sealing between the intermediate zone Z50, situated just above the flange 16, and the clean zone Z3 delimited axially by the outlet face 20b and in communication with the outlet 8 (in this instance an axial outlet) is obtained in a peripheral contact zone. Such annular contact is achieved for example between an edge of a flange for supporting the media 25 and superposed portions of the lateral wall P2. In this instance, an internal engagement edge B3 is provided in an intermediate component 2b, and against this edge the lower face of the edge of the flange comes into abutment. The lid 2c then covers this edge of the flange and can be interposed and compressed between two seals, when the lid 2c is fixed (in this instance screwed) to the intermediate component 2b. This type of fixing of the lid 2c to an intermediate component 2b is illustrated also in
More generally, any type of filtering element 20 may be provided, in this instance in the casing 2, to separate fine particles conveyed at a speed lower than the speed of entry into the respective cyclones 6, thanks to the flared structure of the deceleration members T. The combined total cross-sectional area of the mouths of the exhaust stacks 50 may represent at least 140% of the combined total cross sectional area of the cylindrical passages 15a formed in the inserts 50a. As a preference, the flaring of the top end of the exhaust stacks 50 allows a progressive increase of between 180 and 250% in respect of the outlet passage cross section of each cyclone 6. This results in a very significant decrease in the speed of the particles conveyed in the air flow F2 on the inlet face 20a of the filtering element 20 facing the exhaust stacks 50.
Referring now to
As illustrated in
Referring to
In this instance, the hollow space 24 in which the purified air F8 circulates emerges via the opening of the upper flange 28 toward the rest of the clean zone so as to be removed toward the outlet 8 of the casing 2, preferably maintaining a longitudinal upward direction. The lower flange 27 may be a blind flange, thus allowing the air flow leaving the exhaust stacks 50 to be deflected first of all centrifugally before arriving at the region RP and then filtered centripetally through the media 25″.
In certain embodiments, the casing 2 has an intermediate internal compartment (in this instance between the compartments C1 and C2) above the exhaust stacks 50, in which compartment deflector means 42, 44 are mounted.
In order to avoid residual dust being thrown directly onto the inlet face 20a of the filtering element 20, a wall in the form of a parasol may be provided which serves to guide the flow of air leaving the exhaust stacks 50 onto the internal face of the lateral wall P2 of the casing 2. As a variant, such a deflection wall may consist of a simple flat disk, acting as an impactor. More generally, it is possible to choose a concavity facing up or facing down, or an arched shape similar to that of the central part 17 of the flange 16 to form a deflection wall facing the outlet orifices of the exhaust stacks 50.
With reference to
In the nonlimiting example of
With reference to
In that case, it is possible to use just one component to form the deflection walls shown in
In operation, as illustrated in
The residual dust, with smaller particle size, and the fine particles are then conveyed with the air into the upper compartment C2, via the exhaust stacks 50 and may be deflected before the filtration stage incorporated internally into the casing 2. An insert may be provided, for example to prefilter or to avoid a direct path between the deceleration member T and the filter media 25, 25′. More generally, whatever the structure for incorporating the filtration stage into the upper compartment C2, what is thus formed is an air separation unit that remains effective over time and is highly suited to processing brake dust. The insert may be a deflector, a foam or a similar prefilter, or a perforated mesh.
One of the advantages of the separation device 1 is that it provides effective separation and groups together, in a relatively compact casing, several separation stages including a main separation using numerous cyclones 6. In practice, more than 80% of the solid brake particles (and dust) can be separated by the group of cyclones 6. The use of one or more filtering elements, downstream of such a group of cyclones, advantageously completes the separation by holding back the finest particles.
Through a separation unit combining cyclones 6 and filter media 25, typically within the one same casing 2, it is possible to reduce the very fine particles of road traffic in the knowledge that (at least as far as the West is concerned) 20% of road-traffic fine-particle emissions come from the brakes. It should be obvious to those skilled in the art that the present invention can be embodied in numerous other specific forms without departing from the field of application of the invention as claimed.
For example, although the casing 2 has been described as being generally of cylindrical shape in respect of its lateral wall P2, other geometries may be employed. Also, the lid 2c may be of a different shape and/or incorporate certain functions which have not been illustrated, for example by supporting the filtering element 20 via fixing tabs or similar member with framework for anchoring the filtering element 20 (such as the flange 28 or other suitable part). It will be appreciated that the device 1 allows a great deal of versatility in terms of the way in which the filtration stage is incorporated, it then being possible for the size of the upper compartment C2 to vary according to what is required.
| Number | Date | Country | Kind |
|---|---|---|---|
| 19 02459 | Mar 2019 | FR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/HR2020/050428 | 3/4/2020 | WO |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2020/183092 | 9/17/2020 | WO | A |
| Number | Name | Date | Kind |
|---|---|---|---|
| 2731102 | James | Jan 1956 | A |
| 4478708 | Farnsworth | Oct 1984 | A |
| 5362379 | Helstrom | Nov 1994 | A |
| 7955405 | Smith | Jun 2011 | B2 |
| 11592067 | Arnault | Feb 2023 | B2 |
| 20060254226 | Jeon | Nov 2006 | A1 |
| 20170198772 | Rocca-Serra | Jul 2017 | A1 |
| Number | Date | Country |
|---|---|---|
| 101653345 | Feb 2010 | CN |
| 4240873 | Jun 1994 | DE |
| 19643869 | Oct 2001 | DE |
| 202005006844 | Jul 2005 | DE |
| 202008009717 | Nov 2009 | DE |
| 102017201736 | Aug 2018 | DE |
| 1188672 | Sep 1959 | FR |
| 3046644 | Jul 2017 | FR |
| 2199267 | Jul 1988 | GB |
| 2508539 | Jun 2014 | GB |
| 2518765 | Apr 2015 | GB |
| 100577680 | May 2006 | KR |
| 20090084615 | Aug 2009 | KR |
| Entry |
|---|
| CN 101653345 A. (Year: 2010). |
| DE 19643869 C2. (Year: 2001). |
| International Search Report (with English translation) and Written Opinion (with machine translation) dated Oct. 15, 2020 in corresponding International Application No. PCT/FR2020/050428; 11 pages. |
| Number | Date | Country | |
|---|---|---|---|
| 20220252117 A1 | Aug 2022 | US |
