Particle trapping system

Abstract

The present document relates to a system (1) designed for trapping particles (16) and intended to be provided on braking means (2), said system comprising at least one suction pipe (5) for sucking up particles (16), a collection chamber (8) into which the suction pipe (5) opens, the collection chamber (8) being connected to an external environment (9), through at least a first filter (10) and a second filter (12) each capable of filtering the particles (16) coming from the suction pipe (5) and opening into the chamber (8), and at least first and second independent devices (14, 15) for generating an air flow.

Description

[0001] DESCRIPTION

[0002] Title: Particle capture system

[0003] Disclosure area

[0004] The invention relates to a particle capture system intended to equip braking means.

[0005] State of the art

[0006] Document FR 3 116 001 discloses a particle capture system fitted to a friction braking device.

[0007] The friction braking system consists of a disc rotating around an axis and pads designed to grip and brake the disc by friction. During the braking phase, the abrasion of the pads causes the emission of particles which must be filtered and collected.

[0008] To achieve this, the capture system comprises a suction line equipped with a filter and a fan located downstream of the filter, said line being connected to the braking device. Air and particles are thus sucked in through the line, the air being filtered by the filter so that the particles are collected on the surface of the filter.

[0009] The capture system also includes vibration generation means, associated with the filter, and a collection bin located under the filter.

[0010] In this way, it is possible to remove the layer of particles accumulated on the surface of the filter, by vibration of the filter, the particles detaching from the filter being collected in the collection tank, by gravity.

[0011] Such an operation of unclogging or cleaning the filter increases its lifespan and increases the volume of air and particles that can be re-filtered.

[0012] Such vibration generating means can, however, be relatively expensive and complex to implement. Disclosure Statement

[0013] To overcome the aforementioned problems, the present document proposes a particle capture system intended to equip braking means, comprising at least one particle suction pipe, a collection chamber into which the suction pipe opens, said collection chamber being equipped with at least one first filter and at least one second filter each capable of filtering the particles coming from the suction pipe and opening into the chamber, at least one first and one second device for generating an air flow, capable of generating: at least one air flow from the inside of the chamber to the outside of the chamber, through the first filter and / or the second filter respectively, in a capture operating mode, and / or at least one air flow from the outside of the chamber to the inside of the chamber, through the first filter or the second filter respectively, in an unclogging operating mode.

[0014] The system is configured so that each airflow generating device is controlled independently of each other airflow generating device. This provides greater versatility in the use of the system and ensures optimum suction at all times, as each filter can be unclogged appropriately (for example, without requiring unclogging of another filter that does not require unclogging).

[0015] In a particle collection phase, it is possible to generate an air flow from the chamber to the outside of the chamber, through the first filter and / or the second filter. The particles are thus collected on the first filter and / or on the second filter.

[0016] In order to avoid a drop in suction and capture performance, the capture system also makes it possible to effectively unclog each of the filters. To do this, an air flow is generated from outside the chamber to inside the chamber, through at least one of the filters, so that the particles collected on the surface of the filter detach from the corresponding filter and fall back into the chamber. The first filter and the second filter may be formed by the same filtering part or structure. In such a case, the first filter may be formed by a first zone of said filtering structure and the second filter may be formed by a second zone of said filtering structure.

[0017] The first and second airflow generating devices may be located respectively downstream of the first filter and the second filter relative to the collection chamber.

[0018] The terms upstream and downstream are defined in relation to the direction of airflow in the capture mode of operation.

[0019] In other words, each airflow generating device can be placed between the corresponding filter and the external environment.

[0020] At least one of the devices for generating an air flow may be a fan.

[0021] The first and second airflow generating devices may each be a fan.

[0022] The control means may be capable of varying the speed of each fan independently. This variation may be gradual, for example continuous, from zero rotation speed to maximum rotation speed.

[0023] The system may include a collection bin capable of collecting particles from the first and second filters in unclogging operating mode.

[0024] The collection bin may be located below the collection chamber. The chamber may thus have an opening at the bottom, opening into the collection bin. Sealing means may be provided between said opening of the chamber and the collection bin.

[0025] The system may include means for estimating pressure losses and / or clogging of the first filter and / or the second filter.

[0026] Such means make it possible to precisely estimate the need to unclog one and / or the other of the filters.

[0027] Alternatively, the unclogging modes may be triggered after a certain operating time. Said means for estimating pressure losses and / or clogging may comprise at least one pressure sensor upstream and at least one pressure sensor downstream of at least one of said filters.

[0028] Alternatively, said downstream and downstream pressure sensors may be replaced by at least one differential pressure sensor, capable of measuring a pressure difference between the upstream and downstream of at least one of said filters.

[0029] The terms upstream and downstream are defined in relation to the direction of airflow during the capture or filtering phase. Thus, the upstream side of the filter faces the collection chamber and the downstream side of the filter faces the outside environment.

[0030] It is thus possible to calculate a pressure difference between the upstream and downstream of a filter in order to estimate the degree of clogging of the filter. Indeed, the more clogged the filter, the greater the pressure difference.

[0031] A first discharge line opening into the chamber may extend downstream of the first filter, a second discharge line opening into the chamber extending downstream of the second filter.

[0032] The downstream end of the first discharge pipe and the downstream end of the second discharge pipe may be connected to each other.

[0033] Said downstream ends may be capable of opening into an external environment or of being isolated from said external environment, for example by means of a solenoid valve.

[0034] The particle suction line may include at least one solenoid valve or one non-return valve.

[0035] The solenoid valve can be closed during the unclogging operating mode and can be opened during the capture operating mode.

[0036] Such a solenoid valve is not mandatory. Note that, in the absence of a solenoid valve, the suction line can be sized to generate greater pressure losses than the filters.

[0037] Such a particle capture system may be intended to equip a friction braking device and may equip a vehicle, for example road or rail, or a stationary rotor machine, such as a wind turbine or an industrial machine.

[0038] The suction line may have a first end connected to a friction braking device and a second end opening into the collection chamber.

[0039] The friction braking device may comprise at least one disc capable of pivoting around an axis, and braking means comprising at least one brake pad, capable of coming to bear on the disc so as to brake its rotation by friction.

[0040] At least one filter may be a surface filter, i.e. a filter which clogs preferentially or only in its outermost layer, in particular the outer layer located on the side of the collection chamber. Said filter may comprise a layer of PTFE (Polytetrafluoroethylene) or cellulose nanofibers on the surface.

[0041] The present document also relates to a method of operating a particle capture system according to one of the preceding claims, comprising: at least one capture phase in which at least one air flow is generated by at least one of the devices for generating an air flow, from the chamber to the external environment, through the first filter and / or the second filter, and at least one unclogging phase in which at least one air flow is generated by at least one of the devices for generating an air flow, from the external environment to the chamber, through the first filter or the second filter respectively, in an unclogging operating mode.

[0042] In the case of at least one first fan located downstream of the first filter and at least one second fan located downstream of the first filter, then: in the capture phase, the first fan and the second fan can be started so as to discharge air from the collection chamber to the outside, through the first filter and / or the second filter. The particles are then collected by the corresponding filter(s). in the unclogging phase, only one of the fans can be started, for example the first fan, so that air is drawn into the collection chamber through the second filter so that the particles are detached from the second filter and fall by gravity back into the bottom of the collection chamber. It is then possible to unclog the first filter, by starting only the second fan for example.

[0043] It should be noted that it is possible to carry out the unclogging phase with both fans running, provided that one of the fans generates a greater depression than the other fan, for example.

[0044] In such a case, the air containing particles present in the collection chamber is not likely to escape through the suction line, because a vacuum is generated in the collection chamber during the unclogging phase.

[0045] The unclogging phase can last between 5 seconds and 1 minute, for example, for each filter.

[0046] The duration of the unclogging phase can be shortened if the degree of unclogging of the filter is reached.

[0047] The capture phase can be carried out in particular in the event of braking of the braking device.

[0048] The unclogging phase can be carried out in particular in the event of the braking device disc stopping rotation.

[0049] When the vehicle is stationary with the pads clamped to the disc, the pneumatic resistance of the suction line increases.

[0050] This is advantageous because the air flow drawn through the suction line decreases while the air flow drawn through the filter being cleaned increases.

[0051] Conversely, when the pads are loosened relative to the disc, the pneumatic resistance of the suction line decreases.

[0052] This tends to increase the air flow rate drawn through the suction line. This higher air flow rate allows the pneumatic lines to be cleaned by removing a greater thickness of dust deposited on the surface of the pipes. Brief description of the figures

[0053] Other features and advantages of the present disclosure will become apparent from the following detailed description, with reference to the accompanying drawings in which:

[0054] [Fig. 1] is a schematic view of a particle capture system according to the present document, equipping a braking device, said view illustrating in particular a particle capture phase,

[0055] [Fig. 2] is a view corresponding to Figure 1, illustrating a phase of unclogging a first filter of the capture system,

[0056] [Fig. 3] is a view corresponding to Figure 1, illustrating a phase of unclogging a second filter of the capture system.

[0057] [Fig. 4] is a view corresponding to Figure 1, illustrating an alternative embodiment of the capture system.

[0058] Detailed Description of Disclosure

[0059] Figure 1 represents a particle capture system 1 intended to equip a braking device 2.

[0060] The braking device 2 conventionally comprises a disc 3 capable of rotating about an axis 3a. The disc 3 is coupled in rotation to the wheel of a vehicle or to the rotor of a machine, for example. The braking device 2 further comprises two brake pads 4 arranged on either side of the disc 3, capable of clamping the disc 3 so as to brake it and / or so as to immobilize it in rotation, and capable of releasing the disc 3. Each pad 4 may comprise a sole and a lining.

[0061] In operation, during a braking phase of the disc 3, the abrasion of the linings of the pads 4 causes the emission of particles which must be filtered and collected. For this, the capture system 1 comprises a suction pipe 5 comprising a first end 6 connected to the braking device 2, and a second end 7 opening into a collection chamber 8.

[0062] The collection chamber 8 can be opened at the bottom and open into a collection bin (not visible because Figure 1 is illustrated in top view). It should be noted that in this figure, the disc is illustrated schematically from the side in order to facilitate representation.

[0063] The collection chamber 8 can also be connected to an external environment 9, respectively through a first filter 10 and a first discharge pipe 11, and a second filter 12 and a second discharge pipe 13.

[0064] The first exhaust pipe 11 can be equipped with a first fan 14. The second exhaust pipe 13 can be equipped with a second fan 15.

[0065] The capture system 1 further comprises means for controlling the fans 14, 15, capable of independently controlling the starting or stopping as well as the rotation speeds of each of the fans 14, 15, and therefore the air flow rate and / or the depression at each of the first and second exhaust ducts 11, 13. The control means may be software and / or hardware (dimmer, switch, program, programmable controller, etc.). They may be connected to a central controller of a vehicle. They are configured to independently control each fan.

[0066] Each filter 10, 12 may be a surface filter, that is to say a filter which clogs preferentially or only in its outermost layer (outer layer located on the side of the center or internal volume of the collection chamber into which the suction pipe 5 opens). These are filters comprising for example a layer of PTFE (Polytetrafluoroethylene) or cellulose nanofibers on the surface.

[0067] Figure 1 illustrates a mode of operation for capturing the system. In this mode, at least one fan 14, 15, for example both fans 14, 15, are started, so as to create a vacuum downstream of the filter(s) 10, 12 concerned, so as to create a suction flow of air and particles 16, successively through the suction pipe 5 of the collection chamber 8 and the discharge pipe(s) 11, 13. During such a mode of operation, the particles 16 are retained by the corresponding filter(s) 10, 12, for example on the external surface of said filter(s) 10, 12, located on the side of the collection chamber 8, that is to say opposite the pipes 11, 13.

[0068] Such an operating mode can be used, for example, in a braking phase of the braking device 2.

[0069] Figure 2 illustrates a mode of unclogging the first filter 10. In this mode of operation, the first fan 14 can be stopped while the second fan 15 generates a depression so that air circulates successively through the first pipe 11, the first filter 10, the collection chamber 8, the second filter 12 and the second pipe 13.

[0070] It will be noted that the diameter of the suction line 5 is relatively small so that the pneumatic resistance of the suction line 5 is greater than the combined pneumatic resistance of the first filter 10, the stopped fan 14 and the first line 11. The air is therefore preferentially drawn into the chamber 8 by the first line 11, even if a low flow rate of air can be drawn by the suction line 5.

[0071] The air passing through the first filter 10 makes it possible to separate the particles 16 from the upstream external surface of the first filter 10, so that these particles 16 fall back into the chamber 8 then into the collection tank.

[0072] The first filter 10 can thus be unclogged.

[0073] Figure 3 illustrates a method of unclogging the second filter 12.

[0074] As before, in this mode of operation, the second fan 15 can be stopped while the first fan 14 generates a depression so that air circulates successively through the second conduit 13, the second filter 12, the collection chamber 8, the first filter 10 and the first conduit 11.

[0075] Here again, the pneumatic resistance of the suction line 5 is greater than the combined pneumatic resistance of the second filter 12, the stopped fan and the second line 13. Air is therefore preferentially drawn into the chamber 8 through the second line, even if a low air flow rate can be drawn through the suction line 5.

[0076] The air passing through the second filter 12 makes it possible to separate the particles 16 from the upstream external surface of the second filter 12, so that these particles 16 fall back into the chamber 8 then into the collection tank.

[0077] The second filter 12 can thus be unclogged.

[0078] Figure 4 illustrates an alternative embodiment which differs from the embodiment described above in that the downstream end of the first pipe and the downstream end of the second pipe are connected to each other. A solenoid valve makes it possible to block or release a passage between said pipes and the external environment.

[0079] When the solenoid valve blocks the discharge to the outside environment, the fans operate in a closed circuit. However, the fans used can be more efficient by blowing air rather than sucking air, which increases the cleaning pressure.

Claims

CLAIMS 1. System (1) for capturing particles (16) intended to equip braking means (2), comprising: - at least one suction line (5) for particles (16); - a collection chamber (8) into which the suction pipe (5) opens, said collection chamber (8) being equipped with at least one first filter (10) and at least one second filter (12) each capable of filtering the particles (16) coming from the suction pipe (5) and opening into the chamber (8); - at least one first and one second air flow generation device (14, 15), configured to be controlled independently of one another, and capable of generating: o at least one air flow from the inside of the chamber (8) to the outside of the chamber (8), through the first filter (10) and / or the second filter (12) respectively, in a capture operating mode, and / or o at least one air flow from the outside of the chamber (8) to the inside of the chamber (8), through the first filter (10) or the second filter (12) respectively, in an unclogging operating mode.

2. System (1) according to claim 1, wherein the first and second air flow generating devices (14, 15) are located respectively downstream of the first filter (10) and the second filter (12) relative to the collection chamber (8).

3. System (1) according to one of claims 1 or 2, in which at least one of the devices for generating an air flow is a fan (14, 15).

4. System (1) according to one of claims 1 to 3, comprising a collection tank capable of collecting the particles (16) from the first and second filters (10, 12) in unclogging operating mode.

5. System (1) according to one of claims 1 to 4, comprising means for estimating the pressure losses and / or the clogging of the first filter (10) and / or the second filter (12).

6. System (1) according to claim 5, wherein said means for estimating pressure losses and / or clogging comprise at least one pressure sensor upstream and at least one pressure sensor downstream of at least one of said filters (10, 12).

7. System (1) according to one of claims 1 to 5, in which a first discharge pipe (11) opening into the chamber (8) extends downstream of the first filter (10), a second discharge pipe (13) opening into the chamber (8) extends downstream of the second filter (12), the downstream end of the first discharge pipe (11) and the downstream end of the second discharge pipe (13) being connected to each other, said downstream ends being able to open into an external environment (9) or to be isolated from said external environment (9).

8. System (1) according to one of claims 1 to 7, in which the suction pipe (5) for the particles (16) comprises at least one solenoid valve.

9. Method of operating a system (1) for capturing particles (16) according to one of claims 1 to 8, comprising: - at least one capture phase in which at least one air flow is generated by at least one of the air flow generation devices (14, 15), from the chamber (8) to the external environment (9), through the first filter (10) and / or the second filter (12), and - at least one unclogging phase in which at least one air flow is generated by at least one of the air flow generating devices (14, 15), from the external environment (9) to the chamber (8), through the first filter (10) or the second filter (12) respectively, in an unclogging operating mode.

Images