Device for cleaning a glazed surface

Abstract

The invention proposes a device for cleaning a glazed surface of a detection device in a vehicle, comprising a nozzle supplied with liquid cleaning product, and having a spray head diffusing the liquid in the form of a jet, said spray head having a closed end. Said spray head comprises at least one spray wall provided with at least one hole through which a straight jet exits.

Description

Cleaning device for glass surfaces Technical field of the invention

[0001] The present invention relates to the field of driving assistance devices and, more particularly, to the field of optical detection systems used for this purpose.

[0002] The invention relates more particularly to cleaning devices configured for cleaning an optical sensor of such an optical detection system. Technical background

[0003] An optical detection system is any system comprising optical sensors such as cameras, laser sensors or other sensors based on the emission and / or detection of light in the spectrum visible or invisible to humans, in particular infrared.

[0004] Such optical detection systems are being fitted to an increasing number of motor vehicles in order to either assist the driver of the vehicle in certain driving situations, one of which is well known, parking assistance, or to make the driving of the vehicle autonomous or partially autonomous.

[0005] The driving assistance devices may comprise detection devices which may take the form, for example, of sensors intended to evaluate an environment outside the motor vehicle, or the form of a camera intended to offer the driver visibility of an environment outside the motor vehicle, visually inaccessible from the driver's seat. Such detection devices then comprise at least one glazed surface positioned within the vehicle such that it is capable of capturing the environment outside the motor vehicle, in a desired area.

[0006] For autonomy and / or driving assistance to be as effective as possible, the data provided by the sensor must be of the best possible quality, and it is therefore essential to have a clean glass surface to carry out these data acquisitions.

[0007] To do this, a cleaning device is arranged in the vicinity of an optical detection device (for example the lens of a camera) in order to be able to project, on demand, a fluid so as to remove any dirt deposited on the glass surface of the detection device. This may be dust or insects, for example.

[0008] This cleaning is essential to provide optimal visibility to the sensor or the user of the motor vehicle.

[0009] As is known, such a cleaning device comprises a nozzle hydraulically connected to a fluid storage tank. The fluid is ejected from the nozzle via a distribution orifice, towards the glass surface to be cleaned. The nozzle diffuses the cleaning liquid in the form of a jet.

[0010] During operation, the free end of the nozzle protrudes from the bodywork and is therefore visible from outside the vehicle.

[0011] It is known to use nozzles with a relatively wide jet profile, such as a flat jet or conical jet, allowing for a large radius of action, sweeping the entire width of the glass, and therefore cleaning a large surface, in this case the entire glass surface of the sensor to be cleaned, with a single distribution orifice.

[0012] The flat jet consists of a jet that strikes orthogonally or obliquely on a deflection surface that allows the jet to be reflected flat and with a large width, like a fan.

[0013] The conical jet exits from the cleaning device with a solid or hollow conical shape.

[0014] It is therefore possible to clean the entire surface in question using a single jet and a single nozzle. Using a single nozzle allows you to remain discreet and avoid having too many visible parts protruding from the vehicle's bodywork.

[0015] The disadvantage of this type of nozzle with a flat or conical jet is the use of too large a volume of cleaning fluid. In addition, the width of the jet required to sweep the entire glass surface to be cleaned leads to a reduction in the impact pressure, which leads to a reduction in cleaning efficiency.

[0016] In the current context, where we want to reduce the amount of cleaning fluid used, in order to carry less volume of liquid in the vehicle, and in order not to waste the on-board liquid, a problem arises.

[0017] The aim of the present invention is therefore to provide a cleaning device which can remain discreet and compact and which uses a smaller quantity of cleaning liquid, while offering high cleaning performance.

[0018] The invention therefore relates to a cleaning device for a glass surface of a detection device fitted to a vehicle, comprising a nozzle supplied with liquid cleaning product, and having a spray head diffusing the liquid in the form of a jet, said spray head having a closed end.

[0019] The invention is mainly characterized in that said sprinkler head comprises at least one sprinkler wall provided with at least one hole through which a straight jet emerges.

[0020] The detection device and the cleaning device may be those of a driving assistance device housed within a motor vehicle. For example, the detection device may be a camera or a sensor making it possible to increase the visibility of a user of the motor vehicle on the environment outside said vehicle. Each camera or each sensor has at least one glazed surface exposed to the outside environment. Thanks to its glazed surface, the detection device captures data from the environment outside the motor vehicle. The cleaning device allows the cleaning of the glazed surface of the detection device so that said glazed surface is freed from external pollutants and thus its optical performance is not degraded.

[0021] The cleaning device according to the invention cleans the glass surface with a straight jet. This means that the jet that impacts a surface forms a point on the surface. This point has a very small cross-section, unlike flat and conical jets which have very wide cross-sections.

[0022] The idea behind the invention is to use this straight jet shape, also called "straight point", to have a stronger impact point on the glass surface, so as to be able to better detach stubborn dirt, and this for a constant flow rate through the nozzle. Indeed, the fluid speed is higher than that of the prior art, because the passage section of the hole is smaller, for the same flow rate. The cleaning efficiency is thus improved.

[0023] The number of holes should be defined according to the surface to be cleaned.

[0024] Each hole forms a straight jet at the outlet. All of these straight jets cover the entire glass surface to be cleaned.

[0025] By using one or more holes with a straight jet profile, the quantity of liquid cleaning product to be used is drastically reduced, while retaining a conventional cleaning device, in particular with a pump, a valve, a fluid circulation channel inside the nozzle, etc. Only the spray head differs. It is more compact because the holes are very small compared to the prior art. The part protruding from the vehicle body is thus minimal.

[0026] According to the different embodiments of the invention, which may be taken together or separately: the hole has a diameter of between 50 and 250 µm. For comparison, a hole in a conical jet has a diameter of between 0.3 and 1 mm. the spray wall has a plurality of holes distributed spatially so that their jets cover the majority of the glass surface to be cleaned located opposite. the spray wall has a plurality of holes distributed uniformly. all the holes have the same section. the spray wall is oriented perpendicularly or obliquely to the closed end. the closed end consists of a spray wall. the hole is cylindrical. the spray wall is flat. the spray wall is curved. all the holes are oriented perpendicularly to the spray wall, the straight jets resulting therefrom being perpendicular to the spray wall.all the holes are oriented obliquely to the spray wall, the resulting straight jets being oblique to the spray wall. a part of the holes is oriented perpendicular to the spray wall, and the other part of the holes is oriented obliquely to the spray wall.

[0027] According to an alternative embodiment, said spray head comprises at least one spray wall provided with at least a first type of hole through which an impact jet exits, and at least a second type of hole through which a rinsing jet exits, the cross-section of the hole of the first type being smaller than the cross-section of the hole of the second type, the maximum diameter of the holes of the second type being less than 250 µm. The cleaning device cleans the glass surface using two types of holes, forming two types of jet at the outlet. The first type of hole, whose cross-section is very small, and which allows at the outlet to have a more targeted jet with high impact, that is to say with high pressure on the glass surface. This type of jet is used to loosen stubborn dirt on the glass surface.The second type of hole, whose cross-section remains small, but is slightly larger than that of the first type of hole, and which allows at the outlet to have a less targeted, wider jet, with less impact but a stronger surface rinsing power. This jet is used to rinse the glass surface, for example to remove dust. The combination of these two types of hole allows for efficient cleaning of the glass surface. The cleaning efficiency is thus improved. The flow rate of liquid passing through a hole of the first type is lower than the flow rate of liquid passing through a hole of the second type, because the fluid passage section of a hole of the first type is lower than the passage section of a hole of the second type, for the same fluid speed.

[0028] Thus, it is understood that the second type of hole ensures less impactful cleaning but with greater rinsing power thanks to its higher flow rate. The number of holes is to be defined according to the surface to be cleaned. All of the jets at the nozzle outlet must globally cover the glass surface to be cleaned. These holes of the first type and second type have a diameter of less than 250µm, whereas in the prior art a distribution orifice has a diameter of the order of 0.3 mm to 1 mm. By using these small holes of the first type and second type, the quantity of liquid cleaning product to be used is drastically reduced, while retaining a conventional cleaning device, in particular with a pump, a valve, a fluid circulation channel inside the nozzle, etc. Only the spray head differs. It is more compact because the holes are very small compared to the prior art. The part protruding from the vehicle body is thus minimal.Each jet is straight: this means that the jet that impacts a surface forms a point on the surface. This point has a very small section, unlike flat and conical jets which have very large sections. The idea is to use this form of straight jet, also called "straight point", to have a stronger point of impact on the glass surface, so as to be able to even better detach stubborn dirt, both for holes of the first type and holes of the second type. The spray wall comprises a plurality of holes of the first type distributed spatially on the spray wall so that their jets impact different areas of the glass surface located opposite. The spray wall comprises a single hole of the second type arranged on the spray wall so as to rinse the glass surface located opposite. The hole of the first type is cylindrical and has a diameter equal to or less than 150µm.the second type hole is cylindrical and has a diameter greater than 150µm and less than or equal to 250µm. the liquid flow rate passing through a first type hole is less than the liquid flow rate passing through a second type hole. the nozzle has a single liquid circulation channel, the liquid exiting simultaneously through the first and second types of holes. the nozzle has a first liquid circulation channel opening into the first type hole(s), and a second liquid circulation channel opening into the second type hole(s), said first and second channels being connected to a valve so that the liquid exits either through the first type hole(s) or through the second type hole(s). all the holes are oriented perpendicular to the spray wall, the resulting straight jets being perpendicular to the spray wall.all the holes are oriented obliquely to the spray wall, the resulting straight jets being oblique to the spray wall. a part of the holes is oriented perpendicular to the spray wall, and the other part of the holes is oriented obliquely to the spray wall.

[0029] According to another embodiment, said spray head comprises at least one spray wall provided with holes through which jets emerge, these holes being distributed in groups, each group comprising one or more holes whose jets reach a predefined area of ​​the vehicle, the nozzle having as many liquid circulation channels as there are groups, each channel opening into a group of hole(s), said channels being connected to valves allowing the passage of liquid selectively in a single channel or in several channels. the cleaning device cleans the glazed surface thanks to several holes distributed in several groups. Thus, there is no longer a single distribution orifice as in the prior art, but there is a plurality of distribution orifices, that is to say holes, and thus a plurality of jets. The holes are distributed in groups, in order to concentrate the jets of the same group on a predefined area of ​​the vehicle.There are therefore several groups that clean several areas. Thus, several areas of the vehicle can be cleaned at the same time, with a single spray wall. Thanks to the valves and the different channels within the nozzle, it is possible to send liquid through only one group of hole(s) in order to clean a single predefined area of ​​the vehicle, and thus avoid wasting liquid by sending jets into the other groups.

[0030] For example, if only one area of ​​the glass surface of the detection device is to be cleaned, while the other areas are clean, liquid will only be sent into the channel associated with the group of holes whose jet is directed towards that specific area to be cleaned. The other areas will not be cleaned.

[0031] You can choose to send liquid into one or more channels, depending on the areas to be cleaned.

[0032] The use of multiple groups of holes and multiple channels is also advantageous for adapting to the climatic conditions outside the vehicle. For example, a first group of holes may have one or more jets directed toward the glass surface to be cleaned, and a second group of holes may have one or more jets directed toward an area of ​​the vehicle located next to the glass surface to be cleaned. If the vehicle is not traveling fast, then the first group may be activated via a first channel and its associated valve to send a jet directly toward the glass surface. If the vehicle is traveling fast or there is wind, then the second group may be activated via a second channel and its associated valve to send a jet toward the area located next to it, but which will be deflected by the wind or by the aerodynamic flow toward the glass surface to be cleaned.

[0033] According to this other embodiment, the holes are cylindrical. The holes have a diameter of less than 300 µm. The holes have a diameter of between 50 µm and 250 µm. The valves are connected to a pump, the device comprising a central unit controlling the pump and / or the valves according to input data, such as vehicle speed or outside temperature. For each group, each hole has a specific angular orientation relative to the spray wall, so that the jet leaving it reaches the predefined zone on the vehicle. Each group of hole(s) forms one or more jet(s) capable of impacting an area of ​​the glazed surface, the spray wall comprising as many groups of hole(s) as there are zones to be impacted on the glazed surface. Each jet is straight. Brief description of the figures

[0034] Other characteristics and advantages of the invention will appear during the reading of the detailed description which follows for the understanding of which reference will be made to the appended drawings in which:

[0035] It represents the projection of several different jet shapes;

[0036] This is a perspective view of a nozzle according to the prior art diffusing a flat jet;

[0037] This is a perspective view of a sprinkler according to the invention with a first sprinkler head configuration;

[0038] This is a perspective view of a sprinkler according to a first variant of the invention with a first sprinkler head configuration;

[0039] This is a perspective view of a sprinkler according to the invention with a second sprinkler head configuration;

[0040] This is a perspective view of a sprinkler according to the first variant of the invention with a second sprinkler head configuration;

[0041] This is a perspective view of a sprinkler according to the invention with a 3rd sprinkler head configuration;

[0042] Represents several possible arrangements of holes according to the first variant of the invention;

[0043] It represents the projection of a straight jet from a nozzle according to the invention;

[0044] This is a sectional view of an example of the spray head of a nozzle according to one of Figures 3a to 5a;

[0045] This is a sectional view of an example of the spray head of a nozzle according to one of figures 3b to 5b;

[0046] This is a sectional view of another example of the sprinkler head of a nozzle according to one of Figures 3 to 5;

[0047] This is a detailed view of the holes present on a sprinkler head of a nozzle according to the invention;

[0048] This is a detailed view of the holes present on a sprinkler head of a nozzle according to the first variant of the invention;

[0049] This is a perspective view of a sprinkler according to the invention with a fourth sprinkler head configuration;

[0050] This is a perspective view of a sprinkler according to the first variant of the invention with a fourth sprinkler head configuration;

[0051] This is a sectional view of an example of the sprinkler head of a nozzle according to the;

[0052] This is a sectional view of an example of the sprinkler head of a nozzle according to the;

[0053] This is a perspective view of a sprinkler according to the invention with a fifth sprinkler head configuration;

[0054] This is a perspective view of a sprinkler according to the first variant of the invention with a fifth sprinkler head configuration;

[0055] This is a perspective view of a sprinkler according to the invention with a sixth sprinkler head configuration;

[0056] This is a perspective view of a sprinkler according to the first variant of the invention with a sixth sprinkler head configuration;

[0057] It consists of a graph comparing the performance of a prior art nozzle with a nozzle according to the invention.

[0058] This is a perspective view of a nozzle according to a second variant of the invention;

[0059] This is a perspective and transparent view of the channels inside the nozzle of the;

[0060] This is a schematic view of a hydraulic cleaning circuit according to a first configuration of the second variant of the invention;

[0061] This is a schematic view of a hydraulic cleaning circuit according to a second configuration of the second variant of the invention. Detailed description of the invention

[0062] In the remainder of the description, elements having an identical structure or similar functions will be designated by the same references.

[0063] By convention, the "axial" direction corresponds to that of the main extension of the nozzle, illustrated by the X axis in Figures 3a and 3b, and the "radial" direction is orthogonal to the axial direction. For example, the Y axis is orthogonal to the X axis and thus shows a radial direction.

[0064] In the detailed description of the figures which follow, the terms “upper” and “lower” or “top” and “bottom” will be used in a non-limiting manner in reference to the axial direction.

[0065] It represents the projection of several different jet shapes.

[0066] In this case, representations 1a and 1b show the projection of a flat jet. In representation 1a, the flat jet has a convex distribution, while in representation 1b, the flat jet has a uniform distribution.

[0067] Representations 1c, 1d, 1e show the projection of a conical jet. This conical jet has a convex distribution on representation 1c, a uniform distribution on representation 1d, and a concave distribution on representation 1e.

[0068] These types of flat and conical jet are used in prior art cleaning devices, to clean the glass surface of various optical sensors belonging to detection systems installed on motor vehicles.

[0069] Such a prior art cleaning device is illustrated in. In this case, it is a nozzle 1 hydraulically connected to a cleaning product supply source.

[0070] The cleaning product is a fluid, preferably in liquid form, such as windshield washer fluid. Generally, a pump draws the liquid product from the supply source (in this case a tank) and returns it, via one or more valves, to the nozzle 1, which then diffuses the liquid product in the form of a jet towards the optical sensor located nearby.

[0071] The nozzle 1 has a first end 6 corresponding to a hydraulic connection, and a second free end corresponding to a spray head 2 through which the liquid product is expelled. Here, the liquid product is sprayed in the form of a flat jet with uniform distribution.

[0072] The nozzle 1 extends along a central axis X, from the first end 6 to the spray head 2. The nozzle 1 has an internal channel inside which the liquid product circulates from the first end 6 to the spray head 2.

[0073] The spray head 2 is closed and has an orifice for dispensing the liquid product to diffuse it in the form of a jet, after it has been reflected on a deflection surface located inside the head 2, so as to obtain a flat jet.

[0074] For flat and cone jets, the single distribution orifice must be large enough to provide a wide projection at the outlet, in the order of 0.3mm to 1mm in diameter.

[0075] For conical jets, the distribution orifice must have a particular shape, for example with a first cylindrical section followed by a second conical section flared outwards. It is also possible to provide a swirl chamber inside the spray head opening onto the distribution orifice. It is also possible to provide a nozzle in the spray head, with an anvil arranged inside, so as to form a jet with a certain shape at the outlet. There are many technical solutions.

[0076] These flat and conical jets have the advantage of being able to diffuse the product with a relatively broad spectrum, and therefore of covering at least the entire width of the glass surfaces of the sensors.

[0077] However, the pressure of the liquid product on the glass surface at the time of impact is sometimes not sufficient to remove the most stubborn stains.

[0078] Hence the use of the nozzles 1 according to the invention as illustrated in figures 3 to 13. In these figures, the nozzle 1 used has all the technical characteristics of the nozzle 1 of the prior art, except for the spray head 2.

[0079] The spray head 2 is still closed by means of a closed end 4, but it is simplified to the extreme. In particular, it does not have an internal deflection surface, nor a nozzle, nor anvil, nor a distribution orifice with a complex shape or a large diameter.

[0080] The sprinkler head 2 according to the invention comprises at least one sprinkler wall 3 provided with at least one hole 5 through which a straight jet emerges.

[0081] This is a simple 5 hole, with a uniform section.

[0082] The jet is straight, meaning that its projection corresponds only to a point, as illustrated in.

[0083] Such a straight jet cannot sweep the entire width of a glass surface of a detection device, unless the glass surface is very small. However, with such a straight jet, the pressure is greater at the point of impact, compared to a cone or flat jet. Thus, this type of straight jet can better clean dirty surfaces at the precise point where it impacts.

[0084] The spray wall 3 is oriented towards the detection device to be cleaned located near the nozzle 1.

[0085] According to the invention, each hole 5 has a diameter of between 50 and 250 µm, which is very small compared to the diameter of the dispensing orifices of the prior art. This also makes it possible to be precise at the point of impact on the surface to be cleaned.

[0086] To cover a larger surface area, several holes 5 may be provided in the spray wall 3, in order to distribute the jets over the surface to be cleaned. Preferably, the holes 5 are spatially distributed over the spray wall 3 so that their jets cover the majority of the glass surface to be cleaned located opposite.

[0087] The number of holes 5 to be provided is calculated based on the extent of the surface to be cleaned nearby.

[0088] Preferably, the holes 5 are so small that the total of their sections remains less than the section of a distribution orifice according to the prior art.

[0089] Thus, for the same flow rate passing through the nozzle 1, the pressure of the jet on the glass surface will be significantly greater with a sprinkler head 2 according to the invention than with a sprinkler head 2 according to the prior art.

[0090] This is illustrated in particular in, where the curve with the small circles corresponds to the use of a nozzle 1 according to the prior art, and the curve with the small diamonds corresponds to the use of a nozzle 1 according to the invention. For the same flow rate (in ml / s), the pressure exerted on the surface to be cleaned by the jet emerging from a nozzle 1 according to the prior art is much lower than the pressure exerted on the same surface to be cleaned by the jet emerging from a nozzle 1 according to the invention.

[0091] In fact, the smaller the hole passage section, the greater the fluid velocity for the same volume flow rate. Thanks to this higher fluid velocity (i.e. the speed of interaction with the surface), cleaning efficiency is improved.

[0092] With these small holes, it follows that the consumption of liquid product necessary for cleaning is lower compared to the prior art. Indeed, consumption drops by at least 40%, and up to 60% with a nozzle according to the invention compared to a nozzle according to the prior art, and this while maintaining the same percentage of coverage of the cleaned surface, as shown in the table below.

[0093] Std nozzle corresponds to a nozzle according to the prior art.

[0094] New nozzle corresponds to a nozzle according to the invention.

[0095] The first column specifies the percentage of surface covered by the jets.

[0096] The second column specifies the windshield washer fluid consumption in ml / s.

[0097] The third column compares the liquid consumption between the two types of nozzle, and gives the percentage of liquid used with the nozzle according to the invention. The reduction is approximately 60%.

[0098] The fourth column specifies the fluid velocity at the outlet of the orifice / hole.

[0099] The fifth column compares the fluid velocity between the two types of nozzle, and gives the percentage of additional velocity with the nozzle according to the invention. There is an increase in velocity of approximately 17% to 20%.

[0100] According to a first configuration of the sprinkler head 2 shown in, the sprinkler wall 3 has a plurality of holes 5 distributed uniformly. In this case, there are 36 holes 5 distributed over six columns oriented perpendicular to the X axis, each column comprising six holes 5. Each hole 5 has a diameter of 100 µm.

[0101] According to a second configuration of the sprinkler head 2 shown in, the sprinkler wall 3 has four holes 5 aligned on a single column oriented perpendicular to the X axis. Each hole 5 has a diameter of 200 µm.

[0102] According to a third configuration of the sprinkler head 2 shown in, the sprinkler wall 3 has seven holes 5 aligned on two columns oriented perpendicular to the X axis. The holes 5 are staggered from one column to the other.

[0103] Preferably, whatever the configuration, the holes 5 have the same section.

[0104] However, within the framework of the present invention, it would be possible to provide that the holes 5 do not have the same section depending on their location on the spray wall 3.

[0105] It is understood that there may be a multitude of possible configurations, depending on the number of holes 5, their section, and their positioning on the spray wall 3.

[0106] It will be noted that the holes 5 are preferably arranged in the vicinity of the closed end 4 of the sprinkler head 2. In fact, only the sprinkler head 2 protrudes from the body of the vehicle. The closer the holes 5 are to the closed end 4, the more it will be possible to hide a part of the sprinkler head 2 in the body. This is valid for nozzles fixed in the body. The nozzles of the present invention can also be removable, in particular movable by translation, or even telescopic in order to disappear under the hood.

[0107] In Figures 3 to 5, the spray walls are oriented perpendicular to the closed end 4. However, within the framework of the present invention, it would be possible to provide spray walls oriented obliquely to the closed end 4, that is to say inclined relative to the axis X. The orientation of the spray wall 3 depends in particular on its position relative to the surface to be cleaned.

[0108] In the 3 examples shown in Figures 3 to 5, the sprinkler head 2 has a rectangular section. It is therefore formed of four side walls and an end wall.

[0109] Depending on the relative positioning between the nozzle 1 and the glass surface to be cleaned of the detection device, the holes 5 will be made on one of these five walls. Indeed, it is possible to consider making holes 5 on the end wall if this is more practical for the integration of the nozzle 1 relative to the detection device within the bodywork. Thus the end wall can also correspond to a spray wall 3.

[0110] It is also possible to envisage making holes 5 on several walls of the same nozzle 1, in order to be able to clean simultaneously or alternately several glass surfaces belonging to several detection devices which are located near this nozzle 1. In this case, the spray head 2 has several spray walls 3.

[0111] It is possible to consider having several channels inside the nozzle 1 in order to be able to send liquid selectively towards one or the other spray wall 3 depending on the sensor to be cleaned nearby.

[0112] According to an alternative embodiment shown in, the sprinkler head 2 no longer has a single outlet orifice, but at least two outlet orifices or holes 5 of different types, called first type of hole 5a, and second type of hole 5b.

[0113] These two types of holes 5a, 5b are located on the same sprinkler wall 3.

[0114] The spray head 2 comprises at least one spray wall 3. The spray wall 3 is oriented towards the detection device to be cleaned located near the nozzle 1.

[0115] The spray head 2 could have several spray walls 3 if there are several glass surfaces to be cleaned.

[0116] The first type of hole 5a allows an impact jet to be released.

[0117] The second type of hole 5b allows a rinsing jet to exit.

[0118] The cross-section of the holes of the first type 5a and the second type 5b is less than 0.15mm2, which is very small compared to the prior art.

[0119] So, instead of having a single jet that must cover the entire glass surface, there are several jets that arrive at several areas of the glass surface, so that in the end the cleaning fluid spreads over the entire surface.

[0120] The section of the first type hole 5a is smaller than the section of the second type hole 5b.

[0121] The smaller the passage section of the hole 5, the more the fluid velocity increases for the same volume flow rate. Thanks to this higher fluid velocity (i.e. the speed of interaction with the surface), the point of impact on the glass surface will be higher in terms of impact pressure, compared to the prior art. Thus, the first type holes 5a are mainly used to strongly impact the glass surface at several points, in order to detach stubborn stains.

[0122] The second type 5b holes ensure surface rinsing, with less impact.

[0123] The combination of the two types of holes 5a, 5b improves cleaning efficiency.

[0124] Holes 5 (first type and second type) are simple, with a uniform section.

[0125] Preferably, the holes 5 are cylindrical. But they could have a square or rectangular section.

[0126] These 5 simple holes allow to obtain a straight jet at the exit, which means that its projection corresponds only to a point, as illustrated in.

[0127] According to this embodiment, the holes of the first type 5a have a diameter equal to or less than 150µm. This also allows for precision at the point of impact on the surface to be cleaned.

[0128] For example, holes of the first type 5a have a diameter of 50µm.

[0129] Second type 5b holes have a diameter greater than 150 µm and less than 250 µm.

[0130] The quantity of first type 5a holes to be provided is calculated based on the extent of the surface to be cleaned nearby.

[0131] In addition, there is at least one second type hole 5b in the spray wall 3. This second type hole 5b is arranged on the spray wall 3 so that its jet reaches the glass surface, rinsing it by spreading the fluid over the surface. The orientation of the jet is therefore important to ensure spreading over the entire surface after impact.

[0132] The holes of the first type 5a and of the second type 5b are so small that the total of their sections remains less than the section of a distribution orifice according to the prior art.

[0133] The smaller the hole passage section, the greater the fluid velocity for the same volume flow rate. Thanks to this higher fluid velocity (i.e. the speed of interaction with the surface), cleaning efficiency is improved.

[0134] According to a first configuration of the sprinkler head 2 shown in, the sprinkler wall 3 has a plurality of holes of the first type 5a distributed uniformly. In this case, there are 32 holes 5a distributed over six columns and 6 rows. The sprinkler wall 3 also has a hole of the second type 5b positioned in the center. All the holes are cylindrical.

[0135] According to a second configuration of the sprinkler head 2 shown in, the sprinkler wall 3 has four first-type holes 5a aligned on a single column oriented perpendicular to the X axis, and a second-type hole 5b positioned below the first-type holes 5a. All the holes are cylindrical.

[0136] The (left) shows more precisely this distribution of the holes 5 of the.

[0137] The (right) shows another possible spatial representation of the holes, with a single planetary second-type 5b hole (in the center), and 6 satellite first-type 5a holes (on the periphery). In this example, the first-type 5a holes have a diameter of 100µm, and the second-type 5b hole has a diameter of 250µm. All holes are cylindrical.

[0138] In the spray wall 3, the flow rate passing through a first-type hole 5a is logically reduced compared to the flow rate passing through a second-type hole 5b, but the jet emerging from a first-type hole 5a has a greater impact point. The second-type hole therefore has a greater flow rate, but with less impact, and instead ensures the general rinsing of the glass surface.

[0139] It is understood that there may be a multitude of possible configurations, depending on the number of holes 5a and 5b, their section, and their positioning on the spray wall 3.

[0140] Preferably, the holes 5 are arranged in the vicinity of the closed end 4 of the sprinkler head 2. In fact, only the sprinkler head 2 protrudes from the body of the vehicle. The closer the holes 5 are to the closed end 4, the more it will be possible to hide a part of the sprinkler head 2 in the body. This is valid for nozzles fixed in the body. The nozzles of the present invention can also be removable, in particular movable by translation, or even telescopic in order to disappear under the hood.

[0141] In Figures 3b and 4b, the spray walls are oriented perpendicular to the closed end 4. However, within the framework of the present invention, it would be possible to provide spray walls oriented obliquely to the closed end 4, i.e. inclined relative to the X axis. The orientation of the spray wall 3 depends in particular on its position relative to the surface to be cleaned.

[0142] In the two examples shown in Figures 3b and 4b, the sprinkler head 2 has a rectangular section. It is therefore formed of four side walls and an end wall.

[0143] Depending on the relative positioning between the nozzle 1 and the glass surface to be cleaned of the detection device, the holes 5 will be made on one of these five walls. Indeed, it is possible to consider making holes 5 on the end wall if this is more practical for the integration of the nozzle 1 relative to the detection device within the bodywork. Thus the end wall can also correspond to a spray wall 3.

[0144] It is also possible to envisage making holes 5 on several walls of the same nozzle 1, in order to be able to clean simultaneously or alternately several glass surfaces belonging to several detection devices which are located near this nozzle 1. In this case, the spray head 2 has several spray walls 3.

[0145] It is possible to envisage having several channels inside the nozzle 1 in order to:be able to send liquid selectively towards one or the other spray wall 3 depending on the sensor to be cleaned nearby;be able to send liquid selectively towards the holes of the first type 5a of a spray wall 3, or towards the holes of the second type 5b of this same spray wall 3.

[0146] A valve upstream of the nozzle manages the sending of liquid to the different channels.

[0147] Figures 7 and 8 show a sectional view of these sprinkler heads 2 with rectangular section. In these sectional views, some holes 5 are shown through which liquid product escapes in the form of a straight jet.

[0148] Generally, in all the configurations shown in Figures 3 to 13, the holes 5 are cylindrical, or nearly cylindrical. In most manufacturing processes, the holes are nearly cylindrical, but are slightly flared in a cone shape.

[0149] In the figures shown, the cylindrical holes have a circular section at the outlet.

[0150] However, within the scope of the present invention, the cylindrical holes could have a square, or rectangular, or other section.

[0151] It will be noted that in figures 7a and 7b the holes 5 are oriented perpendicular to the spray wall 3.

[0152] On the, the two central holes 5 are oriented perpendicular to the spray wall 3, while the two lateral holes 5 are oriented obliquely to the spray wall 3.

[0153] When the holes 5 are oriented perpendicular to the spray wall 3, the straight jets resulting from them are perpendicular to the spray wall 3.

[0154] When the holes 5 are oriented obliquely to the spray wall 3, the straight jets resulting from them are oblique to the spray wall 3.

[0155] This applies to both first type 5a holes and second type 5b holes.

[0156] Depending on the case, all the holes 5 can be oriented perpendicular to the spray wall 3, or only some, where all the holes 5 can be oriented obliquely to the spray wall 3, or only some.

[0157] The obliquely oriented holes 5 may be oriented inwards as in (i.e. towards the Y axis), or outwards as in Figures 12a and 12b (i.e. away from the Y axis), or rearwards as shown in Figures 13a and 13b (i.e. towards the first end 6 of the nozzle 1), or forwards (i.e. towards the second end 4 of the nozzle 1), and this in combination.

[0158] The angles are chosen according to the area to be touched with the jet on the surface to be cleaned.

[0159] Figures 9a and 9b show an enlarged view of a spray wall 3 with a plurality of holes 5 of cylindrical section, each hole 5 having a specific orientation, defined according to the surface to be cleaned located nearby, so as to properly direct the jets towards precise locations on the surface.

[0160] In figures 3 to 5, and 7 to 8, the spray wall 3 is flat.

[0161] However, the spray wall 3 could be curved, as illustrated in Figures 10 to 13.

[0162] In particular in Figures 11a and 11b, showing a sectional view of part of the section of the sprinkler head 2 of Figures 10a and 10b, the curved shape of the sprinkler wall 3 in which the holes 5 are made can be clearly seen.

[0163] The use of a nozzle 1 according to a second embodiment of the invention as illustrated in Figures 15 and 16, makes it possible to no longer require the use of a large quantity of cleaning liquid. Indeed, the entire glass surface is cleaned each time the nozzle is activated, even though there is only a small dirty area to clean on the glass surface.

[0164] The use of a nozzle 1 according to the second embodiment of the invention as illustrated in Figures 15 and 16 also makes it possible to no longer waste cleaning liquid. Indeed, when the outside temperature drops, or there is a lot of wind, or the vehicle is traveling at high speed, the jet tends to be deflected and to spray an area located next to the glass surface.

[0165] In these figures, the nozzle 1 used has several inlets E1, E2 for cleaning liquid, each inlet E1, E2 being connected to a cleaning liquid circulation channel which passes through the spray head 2 of the nozzle 1.

[0166] In the example shown, there are two channels C1 and C2. There could be more within the scope of the present invention.

[0167] So the first channel C1 starts at the first input E1, and the channel C2 starts at the second input E2.

[0168] These liquid inlets E1, E2 correspond to hydraulic connections, suitable for connection to valves.

[0169] The channels C1, C2 have a first section extending in a first direction X1, X2, then a second section extending in a second direction Y1, Y2 perpendicular to the first direction X1, X2.

[0170] Other channel paths and orientations are within the scope of the present invention.

[0171] Holes 5 are made in the sprinkler head 2, more precisely at the level of a sprinkler wall 3, and open into the channels C1, C2, at the end of the channels, in their second sections.

[0172] In the example shown, four holes 5 open into the first channel C1, and four holes 5 open into the second channel C2.

[0173] These holes are aligned along axes Y1 and Y2, but they could have another spatial distribution, as long as they open into the corresponding channel.

[0174] The nozzle 1 presented thus comprises a first group G1 of four holes 5 exiting the first channel C1, and a second group G2 of four holes 5 exiting the second channel C2.

[0175] There are as many groups of holes as there are channels.

[0176] When cleaning fluid is injected into inlet E1 of nozzle 1, four jets will come out through the four holes 5 of group G1.

[0177] When cleaning fluid is injected into inlet E2 of nozzle 1, four jets will come out through the four holes 5 of group G2.

[0178] Holes 5 have a uniform section.

[0179] Preferably, the holes 5 are cylindrical, therefore with a circular section.

[0180] But they could have a square or rectangular section.

[0181] There is no deflection surface in the spray head, no nozzle, no anvil, as in the prior art. The holes 5 are simple.

[0182] These 5 simple holes allow to obtain a straight jet at the exit, which means that its projection corresponds only to a point, as illustrated in.

[0183] Such a straight jet cannot sweep the entire width of a glass surface of a detection device, unless the glass surface is very small. However, with such a straight jet, the pressure is greater at the point of impact, compared to a cone or flat jet. Thus, this type of straight jet can better clean dirty surfaces at the precise point where it impacts them.

[0184] So, instead of having a single jet that must cover the entire glass surface, there are several jets that arrive at several areas of the glass surface, so that in the end the cleaning fluid spreads over the entire surface.

[0185] According to this variant embodiment of the invention, the holes 5 have a diameter of less than 300 µm. These are therefore small holes compared to the prior art.

[0186] Preferably, the holes have a diameter between 50µm and 250µm.

[0187] The smaller the passage section of the hole 5, the more the fluid speed increases for the same volume flow rate. Thanks to this higher fluid speed (i.e. the speed of interaction with the surface), the point of impact on the glass surface will be higher in terms of impact pressure, compared to the prior art.

[0188] This also allows for precision at the point of impact on the surface to be cleaned.

[0189] The holes 5 are so small that the total of their sections remains less than the section of a distribution orifice according to the prior art.

[0190] With these small holes, it follows that the consumption of liquid product necessary for cleaning is lower compared to the prior art. Indeed, consumption drops by at least 40%, and up to 60% with a nozzle according to this variant of the invention compared to a nozzle according to the prior art, and this while maintaining the same percentage of coverage of the cleaned surface.

[0191] Each hole 5 has a specific angular orientation relative to the spray wall 3, so that the jet coming out points towards a specific area of ​​the vehicle.

[0192] For example, a hole may be perpendicular to the sprinkler wall 3 and thus send a jet perpendicular to the sprinkler wall 3, or it may be oblique to the sprinkler wall 3 and thus send a jet oriented to the right, or to the left, and / or to the front or to the rear of the sprinkler head 2.

[0193] The angles are chosen depending on the area to be hit with the jet on the vehicle.

[0194] The vehicle has a hydraulic circuit for cleaning the glass surface of a detection device fitted to the vehicle.

[0195] The cleaning liquid is stored in a tank 7. A pump 8 sucks up this liquid and injects it into a network of valves V arranged upstream of the nozzle 1 and connected to the inlets E of the nozzle 1.

[0196] In the first configuration shown in the, the nozzle 1 has four inlets E1, E2, E3, E4 connected to four valves V1, V2, V3, V4.

[0197] These inlets E1, E2, E3, E4 open onto four internal channels C1, C2, C3, C4 running inside the nozzle 1 and leading to groups G1, G2, G3, G4 of holes 5 through which jets emerge when liquid is sent there. In other words, there are four channels.

[0198] The holes 5 are made in the spray wall 3 which is arranged opposite a glass surface of a detection device.

[0199] This glass surface is divided into several zones Z1, Z2, Z3, Z4 to be cleaned.

[0200] There are as many channels as there are areas to clean, and vice versa.

[0201] The areas are thus separated hydraulically thanks to the plurality of tracks.

[0202] Thus, holes 5 of group G1 are oriented so that their jets reach zone Z1, and are distributed over this zone Z1.

[0203] The same applies to holes 5 of groups G2, G3, G4 opposite zone Z2, Z3, Z4.

[0204] If the entire glass surface is dirty, then all areas must be cleaned, and all valves will be opened to allow cleaning fluid to flow through all channels to spray the entire glass surface.

[0205] If only one area is dirty, then only the valve corresponding to the group of holes facing the area in question will be opened, the other valves will be closed. This avoids wasting liquid unnecessarily on areas that do not need to be cleaned.

[0206] If several zones are dirty, then the corresponding valves are opened, the other valves are closed.

[0207] In addition to cleaning only the dirty areas, these are cleaned with several small high-impact jets, therefore with high cleaning performance.

[0208] In the second configuration shown in, the nozzle 1 has two inlets E1, E2 connected to two valves V1, V2.

[0209] These inlets E1, E2 open onto two internal channels C1, C2 running inside the nozzle 1 and leading to groups G1, G2 of holes 5 through which jets emerge when liquid is sent there.

[0210] The holes 5 are made in the spray wall 3 which is arranged opposite a glass surface of a detection device.

[0211] In this example, this glazed surface is not divided; it corresponds to a zone Z1 of the vehicle. It would be entirely possible to divide it as in the previous example.

[0212] A second zone Z2 of the vehicle is located next to zone Z1. This can be a bodywork area for example, or any other part of the vehicle.

[0213] Holes 5 of group G1 are oriented so that their jets reach zone Z1, and are distributed over this zone Z1.

[0214] Holes 5 of group G2 are oriented so that their jets reach zone Z2, and are distributed over this zone Z2 (as illustrated by the dotted lines).

[0215] When the vehicle is stationary or traveling below a threshold speed, of the order of 70 km / h for example, and in the absence of wind, then only valve V1 will be open and cleaning liquid will impact zone Z1 of the glass surface to clean it if necessary.

[0216] When the vehicle is traveling above the threshold speed, or when there is a lot of wind, then the jets coming out of the group of holes G1 are deflected by the aerodynamic flow or by the wind (illustrated by the arrow) and spray an area next to the glass surface. Thus, the cleaning function is inoperative under these conditions, and the cleaning fluid is wasted if the valve V1 is open.

[0217] To overcome this problem, the holes 5 of group G2 are oriented relative to the spray wall 3 so that their jets, which normally reach zone Z2 in the absence of wind or when the vehicle is traveling at a speed below the threshold value, reach zone Z1 by being deflected by the aerodynamic flow or by the wind (as illustrated by the solid lines).

[0218] So, when the vehicle is traveling above the threshold speed, or when there is a lot of wind, valve V1 is closed while valve V2 is open and cleaning liquid will impact zone Z1 of the glass surface to clean it if necessary.

[0219] It is understood that depending on the position of the detection device on the vehicle, the aerodynamic impact will be different, and the orientation of the holes 5 will be adjusted accordingly beforehand.

[0220] The cleaning device comprises a central unit that receives input data from sensors, including a vehicle speed sensor, or an anemometer, or a temperature sensor, which provides information on weather conditions or the vehicle's driving speed. Depending on these external parameters, and whether or not the glass surface of the detection device needs to be cleaned, the central unit controls the pump and / or valves, in order to activate the correct jets on the correct area to be cleaned.

[0221] Valves can be solenoid valves controlled by the central unit. These are active valves, controlled via an electrical system.

[0222] The valves can also be passive valves, which open or close depending on the pressure of the cleaning fluid sent by the pump. For example, if the central unit commands the pump to send fluid to the valves at a pressure between 2 and 3 bars, then only valve V1 opens, while if the pressure is between 3 and 4 bars, then only valve V2 opens.

[0223] Such a choice of valve, active or passive, is also valid for the first configuration presented previously.

[0224] Whatever the configuration, the holes 5 are preferably arranged in the vicinity of the closed end 4 of the sprinkler head 2. Indeed, only the sprinkler head 2 protrudes from the body of the vehicle. The closer the holes 5 are to the closed end 4, the more it will be possible to hide a part of the sprinkler head 2 in the body. This is valid for nozzles fixed in the body. The nozzles of the present invention can also be removable, in particular movable by translation, or even telescopic in order to disappear under the hood.

[0225] The spray head 2 comprises at least one spray wall 3. The spray wall 3 is oriented towards the detection device to be cleaned located near the nozzle 1.

[0226] The spray head 2 could have several spray walls 3 if there are several glass surfaces to clean. It is possible to multiply the channels accordingly.

[0227] According to the present invention, whether the spray wall 3 is flat or curved, the angular orientation of the holes is chosen as explained previously, obliquely or perpendicularly, depending on the position and extent of the target surface to be cleaned, the objective being to have a high coverage rate of the surface to be cleaned.

[0228] Other shapes and other sections of spray heads may fall within the scope of the present invention, provided that the holes 5 allow straight jets to be projected which reach the surface to be cleaned of the detection device.

[0229] The sprinkler heads can be advantageously obtained by additive manufacturing in order to obtain holes of very small section, rather than by drilling them.

[0230] That said, any other manufacturing technique may be considered within the scope of the present invention.

[0231] The configurations shown in the figures cited are only possible examples, in no way limiting, of the invention which on the contrary encompasses the variants of shapes and designs within the reach of those skilled in the art.

Claims

Cleaning device for a glass surface of a detection device fitted to a vehicle, comprising a nozzle (1) supplied with liquid cleaning product, and having a spray head (2) diffusing the liquid in the form of a jet, said spray head (2) having a closed end (4), in which said spray head (2) comprises at least one spray wall (3) provided with at least one hole (5) through which a straight jet emerges. Device according to the preceding claim, in which the hole (5) has a diameter of between 50 and 250 µm. Device according to one of the preceding claims, in which the spray wall (3) has a plurality of holes (5) distributed spatially so that their jets cover the majority of the glass surface to be cleaned located opposite. Device according to one of the preceding claims, in which the spray wall (3) has a plurality of holes (5) distributed uniformly. Device according to one of the preceding claims, in which the spray wall (3) is oriented perpendicularly or obliquely to the closed end (4). Device according to one of claims 1 to 4, in which the closed end (4) consists of a spray wall (3). Device according to one of the preceding claims, in which the spray wall (3) is flat or curved. Device according to claim 1, wherein said spray head (2) comprises at least one spray wall (3) provided with at least one first type of hole (5a) through which an impact jet exits, and at least one second type of hole (5b) through which a rinsing jet exits, the section of the first type hole (5a) being smaller than the section of the second type hole (5b), the maximum diameter of the second type holes (5b) being less than 250µm. Device according to claim 1 or 8, in which the spray wall (3) comprises a plurality of holes of the first type (5a) distributed spatially on the spray wall (3) so that their jets impact different zones of the glazed surface located opposite Device according to one of claims 1, 8 and 9, in which the flow rate of liquid passing through a hole of the first type (5a) is lower than the flow rate of liquid passing through a hole of the second type (5b). Device according to one of the preceding claims, in which all the holes (5, 5a, 5b) are oriented perpendicular to the spray wall (3), the straight jets resulting therefrom being perpendicular to the spray wall (3). Device according to one of claims 1 to 10, in which all the holes (5, 5a, 5b) are oriented obliquely to the spray wall (3), the straight jets resulting therefrom being oblique to the spray wall (3). Device according to one of claims 1 to 10, in which a part of the holes (5, 5a, 5b) is oriented perpendicular to the spray wall (3), and the other part of the holes (5, 5a, 5b) is oriented obliquely to the spray wall (3). Device according to claim 1, wherein said spray head (2) comprises at least one spray wall (3) provided with holes (5) through which jets emerge, these holes (5) being distributed in groups (G1, G2, G3, G4), each group (G1, G2, G3, G4) comprising one or more holes (5) whose jets reach a predefined zone (Z1, Z2, Z3, Z4) of the vehicle, the nozzle (1) having as many channels (C1, C2, C3, C4) for circulation of liquid as there are groups (G1, G2, G3, G4), each channel (C1, C2, C3, C4) opening into a group (G1, G2, G3, G4) of hole(s) (5), said channels (C1, C2, C3, C4) being connected to valves (V1, V2, V3, V4) allowing the passage of liquid selectively in a single channel or in several Device according to the preceding claim 1 or 11, in which the valves (V1, V2, V3, V4) are connected to a pump (7), the device comprising a central unit controlling the pump (7) and / or the valves (V1, V2, V3, V4) as a function of input data, such as vehicle speed or outside temperature.

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