FR3139083A1 - Optical surface cleaning system - Google Patents

Abstract

System for cleaning an optical surface The invention relates to a system for cleaning (1) an optical surface (3) of an optical device (2), this cleaning system comprising: a wiper blade (10) of a window (4), this broom comprising a scraper blade (12) arranged to wipe a wiping zone (6) of the window distinct from the optical surface (3), the broom being provided with a cleaning member (20) configured to come into contact with the optical surface (3), with a view to cleaning it. Figure for abstract: Figure 2

Description

Optical surface cleaning system

The present invention relates to a system for cleaning an optical surface of an optical device, which optical device is in particular assembled with a vehicle window, in particular a windshield.

The vehicle can be land, sea or air.

In certain vehicles, a camera is provided, for example of the infrared type, mounted in an opening in the windshield and which is located outside the sweep of the wiper blade(s). In this case, it is recommended to have specific camera washing systems because there are frequently, after cleaning, drops or pollution remaining such as dust, snow, leaf debris, organic waste, on camera. Drops are also present when it rains.

The invention aims in particular to propose an effective solution for removing possible drops on the optical device, in particular the camera.

• un balai d’essuyage d’une vitre, ce balai comprenant une lame racleuse agencée pour essuyer une zone d’essuyage de la vitre distincte de la surface optique, le balai étant pourvu d’un organe de nettoyage configuré pour venir en contact avec la surface optique, en vue de son nettoyage, et l’organe de nettoyage étant distinct de la lame racleuse de sorte à pouvoir appliquer des pressions de contact différentes respectivement sur la surface optique et la vitre.

The subject of the invention is therefore a system for cleaning an optical surface of an optical device, this cleaning system comprising:

• a blade for wiping a window, this blade comprising a scraper blade arranged to wipe a wiping zone of the window distinct from the optical surface, the blade being provided with a cleaning member configured to come into contact with the optical surface, with a view to cleaning it, and the cleaning member being separate from the scraper blade so as to be able to apply different contact pressures respectively to the optical surface and the window.

In particular, the cleaning member is arranged to apply a contact pressure to the optical surface which is lower than a contact pressure applied by the scraper blade to the window.

The invention thus makes it possible to effectively clean the optical surface, with a contact pressure between the cleaning member and this optical surface, which is high enough to, for example, remove drops of water or dust present on this optical surface. , while being low enough not to damage the optical device and its optical surface by excessive contact pressure which would generate unwanted friction.

The invention thus makes it possible to ensure that the optical surface is sufficiently clean to enable its proper functioning. Indeed, drops could disrupt the detection of electromagnetic waves such as infrared or visible waves by the optical device. The optical surface is in particular the surface through which the waves enter the optical device, this surface being for example facing a lens of the optical device.

This optical device forms an infrared sensor for example. This optical device could also be arranged as a transmitter of electromagnetic waves, for example an infrared transmitter.

The invention also makes it possible to take advantage of the wiper blade to add this additional function of cleaning the optical surface of the optical device. The presence of the cleaning member on the blade thus makes it possible to clean the optical surface using the back and forth movement of the blade which also ensures cleaning of the windshield.

The invention is particularly advantageous when the optical device is assembled with the window, projecting from this window. The invention makes it possible to clean, with reduced contact pressure, the optical surface projecting from the window, which avoids the risk of damaging the optical device or the scraper blade, for example by excessive friction of the brush on the optical surface. Such excessive friction could also generate unwanted noise. The invention makes it possible to avoid all these disadvantages.

Alternatively, the cleaning member is arranged to apply to the optical surface a contact pressure which is greater than or equal to a contact pressure applied by the scraper blade to the window.

According to one of the aspects of the invention, the optical device is assembled with a vehicle window, in particular a windshield. In particular, the optical device protrudes from the windshield.

According to one of the aspects of the invention, the cleaning member and the scraper blade are configured so that only the cleaning member can reach the optical surface to be cleaned, the scraper blade being set back from this optical surface. In other words, the scraper blade has a defined longitudinal extension so that, during the sweeping movement of the broom, the scraper blade never reaches the optical surface. This helps avoid the problems mentioned above.

According to one of the aspects of the invention, the cleaning member comprises a cleaning contact element in contact with the optical surface, this contact element being made of a flexible material chosen in particular from a foam, a sponge, an elastomer , a marker, a brush.

The choice of this type of material allows for a relatively low contact pressure.

According to one of the aspects of the invention, the cleaning member comprises a cleaning contact element having electrostatic properties, for example to remove dust from the optical surface.

According to one of the aspects of the invention, the cleaning contact element comprises a blade, preferably made of rubber, in particular with a profile favorable to aerodynamics, configured to come into contact with the optical surface with a lower pressure than that of the broom scraper blade.

According to one of the aspects of the invention, the cleaning contact element has a longitudinal free edge and the scraper blade also has a longitudinal free edge, these longitudinal free edges, in particular substantially parallel to each other, being at different heights, heights measured in a direction perpendicular to a longitudinal direction of the broom.

The difference in height of these longitudinal free edges corresponds in particular substantially to the height of the optical surface which projects relative to the window.

According to one of the aspects of the invention, the cleaning member comprises a longitudinal extension of an end tip of the broom, and the cleaning contact element is integral with this extension.

The end cap is usually called “Endclip” in English. This end piece may have an aerodynamic profile, and is attached to a mount which carries the scraper blade of the broom.

According to one of the aspects of the invention, the end piece comprises a main body and this longitudinal extension extends from this main body and has a cross section smaller than the cross section of the main body.

According to one of the aspects of the invention, the cleaning contact element, for example a sponge, a brush, a felt-tip pen or a brush, is produced by overmolding material on this extension.

According to one of the aspects of the invention, the cleaning contact element, for example a sponge, a brush, a felt-tip pen or a paintbrush, is a part or several attached parts, for example by snap-fastening, onto this extension.

According to another aspect of the invention, the end piece is crossed by an extension of at least one vertebra of the broom, this vertebra extension serving to hold the cleaning contact element.

In this case, the cleaning member is notably formed by this extension of the vertebra and the cleaning contact element which is mounted on this vertebra.

According to one of the aspects of the invention, the broom has a total length in a longitudinal direction, a length chosen so that one of its end tips passes directly above the optical surface to be cleaned.

According to one of the aspects of the invention, the cleaning member is formed by this end piece which carries the cleaning contact element.

According to one of the aspects of the invention, the end piece comprises a main body which passes directly above the optical surface to be cleaned.

According to one of the aspects of the invention, this main body is arranged to be mounted at one end of a longitudinal mount which carries a scraper blade, and the main body has an aerodynamic profile.

According to one of the aspects of the invention, the main body has an insertion side which is provided with an insertion opening arranged to allow the insertion of the longitudinal frame into the end piece.

According to one of the aspects of the invention, the broom mount comprises a longitudinal slot in which a portion of the scraper blade is secured.

According to one of the aspects of the invention, the frame of the broom has a length in the longitudinal direction of the broom, a length chosen so that a region of this frame passes directly above the optical surface to be cleaned during operation. get out.

According to one of the aspects of the invention, the longitudinal slot in which a portion of the scraper blade is secured, extends into this region of the frame which passes directly above the optical surface, through a slot in which is fixed the cleaning contact element, in particular a foam, a sponge, an elastomer, a felt-tip pen or a brush.

According to one of the aspects of the invention, the main body of the tip comprises the fixing element of the cleaning contact element, this fixing element comprising in particular a longitudinal slot for holding the cleaning contact element , in particular a foam, a sponge, an elastomer, a felt-tip pen or a brush.

Thus, the cleaning contact element, in particular a foam, a sponge, an elastomer, a felt-tip pen or a brush, can be held on the frame and/or the main body of the end cap. In other words, the general structure of the broom is longer than the sweeping outline, but the scraper blade, for example made of rubber, is limited to this outline. The remaining available space of the broom, at its exterior longitudinal end, is used to maintain the cleaning contact element, in particular a foam, a sponge, an elastomer, a felt-tip pen or a brush.

According to one of the aspects of the invention, to clean the optical surface, the cleaning system comprises, in addition to the cleaning contact element, a nozzle configured to project a jet of fluid, for example air and /or cleaning liquid, on the optical surface to be cleaned.

According to one of the aspects of the invention, the cleaning member comprises a cleaning contact element configured to be deformable between a retracted position in which the cleaning member is moved away from the window so that it can pass to the -above the optical surface without touching it, and a cleaning position in which the cleaning member comes into contact with the optical surface.

According to one of the aspects of the invention, the cleaning member comprises a deformation element configured to cause a deformation of the cleaning contact element, bringing it from its retracted position to its cleaning position, or from its cleaning position to its retracted position.

According to one of the aspects of the invention, the deformation element is configured to deform reversibly.

According to one of the aspects of the invention, the deformation element is configured to deform when subjected to electrical excitation, and to return to a rest position in the absence of electrical excitation.

According to one of the aspects of the invention, the deformation element is connected to an electrical power source, in particular external to the broom, via a bundle of electrical wires carried by the broom.

According to one of the aspects of the invention, the passage of electric current in the deformation element is controlled by a control unit on board the vehicle.

According to one of the aspects of the invention, the deformation element has shape memory capable of deforming when heated, for example by being passed through by an electric current.

Thus, the cleaning contact element takes its cleaning position when the deformation element is deformed under electrical excitation, and the cleaning contact element takes its retracted position when the deformation element is at rest, in absence of electrical excitation.

According to one of the aspects of the invention, the deformation element is at least partially embedded in the cleaning contact element which is flexible, so that the deformation element and the cleaning contact element are linked in deformation. Thus a deformation of the deformation element causes a deformation of the cleaning contact element.

According to one of the aspects of the invention, the deformation element comprises at least one wire with shape memory material, capable of deforming when an electric current is applied.

According to one of the aspects of the invention, the wire has a substantially rectilinear shape in the absence of passage of electric current, and an arcuate shape when an electric current passes through this wire.

This arc shape causes a corresponding deformation of the cleaning contact element, which deforms as it approaches the optical surface to be cleaned.

According to one aspect of the invention, the deformation of the cleaning contact element increases its height so that it can reach the optical surface to be cleaned. In other words, the cleaning contact element is then, as it were, deployed.

According to another aspect of the invention, the deformation element comprises a piezoelectric material, namely a material configured to deform when an electric current is applied to it and to return to its initial shape when it is no longer traversed. by this electric current. Thus when the piezoelectric deformation element is deformed under the action of an electric field, this deformation causes a deformation of the cleaning contact element tending to bring it into contact with the optical surface to be cleaned. This is then put into the cleaning position.

The invention also relates to a broom end cap comprising a main body provided with a fixing element for the cleaning contact element, this fixing element comprising in particular a longitudinal slot for holding the contact element cleaner, in particular a foam, a sponge, an elastomer, a felt-tip pen or a brush.

• lorsque le nettoyage de la surface optique est commandé, mettre en mouvement le balai d’essuyage de sorte que l’organe de nettoyage vienne en contact avec la surface optique pour la nettoyer.

The invention also relates to a method of cleaning an optical surface of an optical device using a cleaning system as described above, this cleaning method comprising the following step:

• when cleaning of the optical surface is ordered, set the wiping blade in motion so that the cleaning member comes into contact with the optical surface to clean it.

• lorsque le nettoyage de la surface optique est commandé, activer la déformation de l’élément de déformation provoquant la déformation de l’élément de contact nettoyant qui vient au contact de la surface optique au cours du mouvement de balayage du balai.

In the case where the cleaning member comprises a deformation element, the method may include the following step:

• when cleaning of the optical surface is commanded, activating the deformation of the deformation element causing the deformation of the cleaning contact element which comes into contact with the optical surface during the sweeping movement of the broom.

According to one of the aspects of the invention, in the case where the deformation element is electrically activatable, an electrical supply is triggered, and the heating of the deformation element deforms it, which unfolds the deformation element. cleaning contact protruding from the end tip and brings it into contact with the optical surface of the optical device.

When the optical surface is cleaned and clean, or after a predefined number of cycles, the power supply turns off and the deforming element returns to its free position, which folds the cleaning contact element.

According to one of the aspects of the invention, the cleaning command results for example from a self-test of the optical device or from an instruction from a vehicle control unit such as the Body Controller Module (BCM) of the vehicle, or any other automatic command.

Other characteristics and advantages of the invention will appear more clearly on reading the following description, given by way of illustrative and non-limiting examples, and the appended drawings among which:

- there illustrates, schematically and partially, a cleaning system according to an example of implementation of the invention;

- there illustrates, schematically and partially, in detail, the cleaning member of the cleaning system of the ;

- there illustrates, schematically and partially, in a view in the longitudinal direction, the cleaning member of the ;

- there illustrates, schematically and partially, a cleaning member according to another example of implementation of the invention;

- there illustrates, schematically and partially, a cleaning member according to another example of implementation of the invention;

- there illustrates, schematically and partially, a detail of the cleaning member of the ;

- there illustrates, schematically and partially, in a view in the longitudinal direction, a cleaning member according to another example of implementation of the invention, in a retracted position;

- there illustrates, schematically and partially, the cleaning member of the in a view perpendicular to the longitudinal direction;

- there illustrates, schematically and partially, the cleaning member of the , in a cleaning position;

- there illustrates, schematically and partially, the cleaning member of the in a view perpendicular to the longitudinal direction.

We represented, on the , a cleaning system 1 of an optical surface 3 of an optical device 2, which optical device 2 is assembled with a vehicle windshield 4.

As visible on the , the optical device 2 is assembled with the windshield 4, projecting from this windshield 4.

The optical surface 3 is the surface through which the waves enter the optical device 2, which in the example described forms an infrared sensor.

The optical device 2 can be a LIDAR (corresponding in English to “Light detection and ranging”), namely a distance measuring device based on the analysis of the properties of a beam of light returned to its transmitter. The optical device can be any type of camera.

The cleaning system 1 comprises a wiping blade 10 arranged to wipe a wiping zone 6 of the windshield 4 distinct from the optical surface 3.

As visible on the , this wiper blade 10 comprises a scraper blade 12, a longitudinal mount 14 to which the scraper blade 12 is secured and an end piece 15 mounted on the mount 14.

This frame 14 is made in particular by extrusion of a plastic material.

This blade 10 is mounted on a wiper arm 16 via a connection device 17 configured to securely fix the wiper blade 10 to the wiper arm 16.

An electric motor 18 is provided to operate the arm 16.

The brush 10 is provided with a cleaning member 20 configured to come into contact with the optical surface 3, with a view to cleaning it, by applying to this optical surface 3 a contact pressure which is lower than a contact pressure applied by the scraper blade 12 on the window 4.

The cleaning member 20 is separate from the scraper blade 12 so as to be able to apply different contact pressures respectively to the optical surface 3 and the window 4.

The cleaning member 20 and the scraper blade 12 are configured so that only the cleaning member 20 can reach the optical surface 3 to be cleaned, the scraper blade 12 being set back from this optical surface 3. In other words, the blade scraper 12 has a defined longitudinal extension so that, during the sweeping movement of the broom, the scraper blade 12 never reaches the optical surface.

As can be seen in Figures 2 and 3, the cleaning member 20 comprises a cleaning contact element 21 in contact with the optical surface 3, this contact element 21 being made of a flexible material chosen in particular from a foam, a sponge, an elastomer, a marker, a brush. The choice of this type of material allows for a relatively low contact pressure.

The cleaning contact element 21 has a substantially triangular cross section (visible on the ) with a longitudinal free edge 22 and the scraper blade 12 also has a longitudinal free edge 19, and these longitudinal free edges 22 and 19, substantially parallel to each other, are at different heights, heights measured in a direction Z perpendicular to an axis longitudinal X of the brush 10, as can be clearly seen on the .

The difference in height of these longitudinal free edges 22 and 19 corresponds substantially to the height h of the optical surface 3 which projects relative to the window 4.

Alternatively, the cleaning contact element 21 may have an arcuate cross section instead of the triangular section. Generally speaking, any other shape of section is possible, which is appropriate to limit the stress and the impact when the element 21 approaches the optical surface 3.

The cleaning member 20 comprises a longitudinal extension 24 projecting longitudinally from the end piece 15, parallel to the axis X, and the cleaning contact element 21 is integral with this extension 24.

The end cap 15 is usually called “Endclip” in English. This end piece 15 may have an aerodynamic profile, and is fixed on one end of the frame 14 which carries the scraper blade 12 of the broom. Another end cap is fixed on the other end of the frame 14.

The end piece 15 comprises a main body 26 and this longitudinal extension 24 extends from this main body 26 and has a cross section smaller than the cross section of the main body 26. This longitudinal extension 24 can be produced in one piece with the tip 15, for example made of plastic.

The cleaning contact element 21 can be produced by overmolding material on this extension 24, or the cleaning contact element 21 is a part or several attached parts, for example by snap-fastening, on this extension 24.

In another example of embodiment illustrated in , the end piece 15 is crossed by an extension of a vertebra 27 of the broom, this extension of vertebra 27 serving to hold the cleaning contact element. This vertebra extension 27 thus replaces this longitudinal extension 24 previously described. The vertebra is a part which reinforces the frame 14, in a known manner.

In another embodiment of the invention illustrated in Figures 5 and 6, the brush 10 has a total length in the longitudinal direction optic 3 to clean.

The cleaning member 30 is formed by this end piece 15 which carries the cleaning contact element 31.

The end piece 15 comprises a main body 33 which passes directly above the optical surface 3 to be cleaned, and this main body 33 has an insertion side 35 which is provided with an insertion opening arranged to allow the insertion of the longitudinal mount 14 into the end piece 15.

The mount 14 comprises a longitudinal slot 36 in which the scraper blade 12 is retained and which extends into this region of the mount 14 which passes directly above the optical surface 3, by a slot 37 in which the cleaning contact element 31, in particular a foam, a sponge, an elastomer, a felt-tip pen or a brush.

The main body 33 of the end piece 15 also includes a slot 39 for retaining the cleaning contact element 31. This cleaning contact element 31 comprises a retaining portion 40 housed in a cavity 41 of the main body 33 of the tip 15, as illustrated on the .

Thus the cleaning contact element 31 is retained by the slot 39 of the end piece 15 and the slot 37 of the frame 14.

Of course, the invention is applicable to a broom with a single vertebra (also called “Spline” in English) or a broom with two vertebrae.

In another embodiment of the invention illustrated in Figures 7 to 10, the cleaning member 50 comprises a cleaning contact element 51 configured to be retractable between a retracted position or rest position (position illustrated in Figures 7 and 8) in which the cleaning member 50 is distant from the window 4 so that it can pass above the optical surface 3 without touching it, and a cleaning position (position illustrated in Figures 9 and 10) in which the cleaning member 50 comes into contact with the optical surface 3.

The cleaning member 50 comprises a deformation element 52 configured to cause a deformation of the cleaning contact element 51, bringing it from its retracted position to its cleaning position, or from its cleaning position to its retracted position.

The deformation element 52 comprises a wire with shape memory material, capable of deforming when heated, by being passed through an electric current. This wire 52 is embedded in the mass of the cleaning contact element 51 which is flexible, so that the deformation element 52 and the cleaning contact element 51 are linked in deformation. Thus a deformation of the deformation element 52 causes a deformation of the cleaning contact element 51.

The wire 52 has a substantially rectilinear shape in the absence of passage of electric current ( ), and an arc shape when an electric current passes through this wire ( ).

This arcuate shape causes a corresponding deformation of the cleaning contact element 51, which deforms as it approaches the optical surface 3 to be cleaned. The deformation of the cleaning contact element 51 increases its height so that it can reach the optical surface 3 to be cleaned.

Thus, the cleaning contact element 51 takes its cleaning position when the deformation element 52 is deformed under electrical excitation, and the cleaning contact element 51 takes its retracted position when the deformation element 51 is at rest , in the absence of electrical excitation.

The deformation element 52 is connected to an electrical power source (not shown), external to the brush, via a bundle of electrical wires 55 carried by the brush 10. The passage of electric current in the deformation element 52 is controlled by a control unit on board the vehicle.

When the cleaning of the optical surface 3 is commanded, the control unit activates the deformation of the deformation element 52 causing the deformation of the cleaning contact element 51 which comes into contact with the optical surface 3 during the movement sweeping the broom.

When the optical surface 3 is cleaned and clean, or after a predefined number of cycles, the electrical power is cut off and the deformation element 52 returns to its rest position, which folds the cleaning contact element 51.

The cleaning command arises for example from a self-test of the optical device or from an instruction from a vehicle control unit such as the vehicle's Body Controller Module (BCM), or from any other automatic command.

In the example which has just been described, the deployment of the cleaning contact element 51 is done vertically. It is possible, as a variant, to have a longitudinal deployment along the axis X of the cleaning contact element 51. The deformation element 52 is then configured to extend the cleaning contact element 51 along the axis in case of need to clean the optical surface 3. When cleaning is not necessary, the cleaning contact element 51 is folded longitudinally in the end piece 51, so as not to touch the optical surface 3.

Claims (12)

System for cleaning (1) an optical surface (3) of an optical device (2), this cleaning system comprising:

• a wiping blade (10) of a window (4), this blade comprising a scraper blade (12) arranged to wipe a wiping zone (6) of the window distinct from the optical surface (3), the blade being provided with a cleaning member (20; 30; 50) configured to come into contact with the optical surface (3), with a view to cleaning it, and the cleaning member (20; 30; 50) being distinct from the scraper blade (12) so as to be able to apply different contact pressures respectively to the optical surface (3) and the window (4).

System according to the preceding claim, in which the cleaning member (20; 30; 50) is arranged to apply to the optical surface (3) a contact pressure which is lower than a contact pressure applied by the scraper blade (12). ) on the window (4). System according to one of the preceding claims, in which the cleaning member (20; 30; 50) comprises a cleaning contact element (21; 31; 51) with the optical surface, this contact element being made of a material flexible chosen in particular from a foam, a sponge, an elastomer, a felt-tip pen, a brush. System according to one of the preceding claims, in which the cleaning contact element (21) has a longitudinal free edge (22) and the scraper blade (12) also has a longitudinal free edge (19), these longitudinal free edges, in particular substantially parallel to each other, being at different heights, heights measured in a direction (Z) perpendicular to a longitudinal direction (X) of the broom. System according to one of the preceding claims, in which the cleaning member comprises a longitudinal extension (24) of an end tip (15) of the broom, and the cleaning contact element (21) is integral with this extension. System according to one of claims 1 to 4, in which an end piece (15) is crossed by an extension of at least one vertebra (27) of the brush, this vertebra extension serving to hold the contact element cleaner. System according to one of claims 1 to 4, in which the blade has a total length in a longitudinal direction (X), length chosen so that one of its end tips (15) passes directly above the the optical surface (3) to be cleaned. System according to the preceding claim, in which the cleaning member (50) comprises a cleaning contact element (51) configured to be deformable between a retracted position in which the cleaning member (50) is moved away from the window so that it can pass over the optical surface (3) without touching it, and a cleaning position in which the cleaning member comes into contact with the optical surface. System according to the preceding claim, in which the cleaning member comprises a deformation element (52) configured to cause deformation of the cleaning contact element (51), bringing it from its retracted position to its cleaning position, or from its cleaning position to its retracted position. System according to the preceding claim, in which the deformation element comprises at least one wire (52) with shape memory material, capable of deforming when an electric current is applied. System according to claim 9, in which the deformation element comprises a piezoelectric material, namely a material configured to deform when an electric current is applied to it and to return to its initial shape when it is no longer traversed by this Electric power. Broom end tip (15) comprising a main body provided with a fixing element for the cleaning contact element, this fixing element comprising in particular a longitudinal slot for holding the cleaning contact element (31), notably a foam, a sponge, an elastomer, a felt-tip pen or a brush.