Abstract:
A wiper assembly for a window of a vehicle and a method of cleaning a window are provided. The wiper assembly includes a wiper blade having a fluid extraction opening, a fluid discharge outlet remote from the wiper blade and a fluid tight conduit connecting the fluid extraction opening to the fluid discharge outlet. The wiper assembly may further include a suction pump configured to draw air and water into the fluid extraction opening and through the fluid tight conduit of the wiper assembly, thereby reducing the amount of water left of the window following wiping and improving visibility for the driver.

Description:
TECHNICAL FIELD 
       [0001]    The present disclosure relates to a wiper assembly for a vehicle. 
       BACKGROUND 
       [0002]    Windscreen wipers are essential components of a vehicle for ensuring the driver has unimpaired vision in all conditions. Windscreen wipers typically comprise rigid arms which sweep back and forth across the windscreen or tailgate glass. The rigid arms are typically configured to support wiper blades which comprise a rubber wiper portion held in contact with the glass of the windscreen or tailgate as the wiper arm sweeps across. 
         [0003]    In wet conditions, wiper blades scrape any water which has settled on the windscreen or tailgate glass to the edge of the glass where it can drain away and does not obstruct the vision of the driver. 
         [0004]    In dry weather, windscreen wipers allow the windscreen to be cleaned of dirt and grease by firstly spraying water or a cleaning solution onto the windscreen or tailgate glass, then operating the wipers to wipe away the water together with any dirt and grease which has become suspended in the water. 
         [0005]    Even the best conventional wiper blades leave droplets of water on the windscreen or tailgate glass when operating. This may be particularly apparent when the windscreen or tailgate glass is especially dirty or greasy. Over time the performance of the wiper blades deteriorates, as the material of the blade is degraded by dirt, oil, sunlight, ozone and airborne contaminants. If the material of the blade has deteriorated, the blade may not maintain contact with the glass across the full length of the blade during its full traverse over the windscreen or tailgate glass and hence the performance of the system may be reduced. The amount of water, dirt and grime which is left on the windscreen may gradually become more noticeable to the driver, and may begin to impair the driver&#39;s vision. 
       SUMMARY 
       [0006]    According to an aspect of the present disclosure there is provided a wiper assembly for a window of a vehicle, such as a motor vehicle, the assembly comprising: a wiper blade having a fluid extraction opening; and a suction pump, configured to draw air and water through the fluid extraction opening of the wiper blade away from the window of the vehicle. This arrangement reduces the amount of water left on the window following wiping, and improves visibility for a driver of the vehicle. 
         [0007]    The term ‘window of a vehicle’ in this specification is intended to encompass any surface of a vehicle and in particular a windscreen, rear screen, tailgate window, side windows, sun roof, mirrors, light lenses or any transparent, translucent or reflective surface of the vehicle. 
         [0008]    The term ‘suction pump’ in this specification is intended to encompass a simple venturi, a venturi pump or any other form of pump such as a piston, rotary or peristaltic pump. 
         [0009]    The wiper assembly may further comprise a fluid tight conduit connecting the fluid extraction channel to a fluid discharge outlet, the fluid discharge outlet being remote from the wiper blade. 
         [0010]    According to an aspect of the present disclosure, there is provided a wiper assembly for a window of a vehicle, such as a motor vehicle, the assembly comprising: a wiper blade having a fluid extraction opening; a fluid discharge outlet remote from the wiper blade; and a fluid tight conduit connecting the fluid extraction opening to the fluid discharge outlet. 
         [0011]    The fluid extraction opening may comprise an elongate slot extending along a length of the wiper blade, e.g. partially or fully along the full length of the wiper blade. The wiper assembly may further comprise one or more additional extraction openings. 
         [0012]    The wiper blade may comprise one or more internal channels in fluidic communication with the extraction opening or openings. The internal channels may be configured to connect the extraction opening to the fluid tight conduit. Each of the one or more internal channels may be in fluidic communication with a different one of the extraction openings or a different subset of the extraction openings to the others of the one or more channels. 
         [0013]    The wiper blade may comprise a leading surface and a trailing surface. The leading and/or trailing surface of the wiper blade may comprise one or more serrations. At least one of the one or more serrations may be substantially aligned with the fluid extraction opening. 
         [0014]    The wiper assembly may further comprise a water/air separator provided upstream of the fluid discharge outlet. 
         [0015]    The wiper assembly may further comprise a pump configured to draw air and water into the fluid extraction opening and through the fluid tight conduit of the wiper assembly, thereby reducing the amount of water left of the window following wiping and improving visibility for a driver of the vehicle. The suction pump may be powered by a supply of ram air provided on the vehicle. The fluid tight conduit may comprise a flexible tube. 
         [0016]    The wiper assembly may further comprise a water sensor, and/or a dirt sensor configured to measure the amount of water and/or dirt present on the surface being wiped. 
         [0017]    According to another aspect of the present disclosure, there is provided a method for removing water from a window of a vehicle, the method comprising: providing a wiper blade including a fluid extraction opening; and a suction pump; and operating the suction pump to draw air and water through the fluid extraction opening of the wiper blade away from the window of the vehicle. 
         [0018]    According to another aspect of the present disclosure, there is provided a method for removing water from a window of a vehicle, the method comprising: providing a wiper blade including a fluid extraction opening; and a fluid discharge outlet remote from the wiper blade; and connecting the fluid extraction opening to the fluid discharge outlet with a fluid tight conduit. 
         [0019]    The method may further comprise: providing a pump configured to draw air and water through the fluid extraction opening of the wiper blade. 
         [0020]    The method may further comprise: coordinating the operation of the suction pump with the operation of an actuation unit configured to control the motion of the wiper blade. 
         [0021]    The method may further comprise monitoring the presence of water and/or dirt on the vehicle window, and adjusting the operation of the suction pump accordingly. For example by increasing the amount of time that the suction pump operates, if the amount of water and/or dirt present increases. 
         [0022]    According to another aspect of the present disclosure, there is provided a controller configured to perform the method according to any of the previously mentioned aspects of the disclosure. 
         [0023]    According to another aspect of the present disclosure, there is provided software, which when executed by a computing apparatus causes the computing apparatus to perform the method according to any of the previously mentioned aspect of the disclosure. 
         [0024]    According to another aspect of the present disclosure, there is provided a vehicle comprising the wiper assembly according to any of the previously mentioned aspects of the disclosure. 
         [0025]    To avoid unnecessary duplication of effort and repetition of text in the specification, certain features are described in relation to only one or several aspects or embodiments. However, it is to be understood that, where it is technically possible, features described in relation to any aspect or embodiment may also be used with any other aspect or embodiment. 
     
    
     
       DESCRIPTION OF THE DRAWING FIGURES 
         [0026]    For a better understanding of the present disclosure, and to show more clearly how it may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: 
           [0027]      FIG. 1  is a schematic sectional view of a vehicle wiper assembly according to an example of the present disclosure; and 
           [0028]      FIG. 2  is a schematic sectional view of a wiper blade for a wiper assembly of a vehicle according to an example of the present disclosure. 
           [0029]      FIG. 3  is a detailed elevational view showing an embodiment of the vehicle wiper assembly including serrations at spaced locations of the wiper portion. 
       
    
    
     DETAILED DESCRIPTION 
       [0030]    A vehicle, such as a motor vehicle, may comprise a windscreen  2  and a windscreen wiper assembly  10 . With reference to  FIG. 1 , the vehicle wiper assembly  10 , according to an example of the present disclosure, comprises a wiper arm  12  and a wiper blade  14 . The wiper arm  12  is configured to couple to the wiper blade  14  at a first end of the wiper arm. 
         [0031]    As illustrated in  FIG. 2 , the wiper blade  14  comprises a flexible wiper portion  14   a.  The wiper arm  12  and wiper blade  14  are together configured such that the wiper portion  14   a  maintains contact with the windscreen  2 , as the wiper blade is passed across the windscreen  2 . 
         [0032]    In order to maintain contact between the wiper blade  14  and the windscreen  2 , the wiper blade  14  may be pivotally connected to the wiper arm  12 , and the wiper arm  12  may include a resilient element such as a spring (not show) which acts to hold the wiper arm  12  and the wiper blade  14  against the windscreen. The wiper blade  14  itself may be resilient or may comprise one or more resilient elements (not shown) which act to curve the wiper portion  14   a  of the wiper blade  14  in order to adapt it to the shape of the windscreen  2 , and thereby maintain contact between the wiper portion  14   a  and the windscreen  2  across the full length of the wiper blade. 
         [0033]    The wiper assembly  10  of  FIG. 1  further comprises a wiper motor and actuator assembly  16 , which is coupled to a second end of the wiper arm  12 . The wiper motor and actuator assembly  16  is operable to control the movement of the wiper arm  12  to sweep the wiper blade  14  across the windscreen  2 . 
         [0034]    As the wiper blade  14  is moved across the windscreen  2 , the wiper portion  14   a  scrapes across the surface of the windscreen sweeping any water or dirt present on the windscreen toward the sides of the windscreen. Additionally, water may collect on the wiper portion  14   a  as it moves across the windscreen  2  and may run down the wiper blade  14  to the bottom of the windscreen. In this way the wiper assembly  10  acts to maintain good visibility for a driver of the vehicle. 
         [0035]    The driver may operate the windscreen wipers during bad weather for the removal of precipitation such as rain water from the windscreen  2 . The driver may also use the windscreen wipers together with a windscreen washer (not shown) which introduces water or a cleaning solution onto the windscreen, allowing dirt to be loosened by the windscreen wipers and carried away with the water. 
         [0036]    As the wiper blade  14  moves across the windscreen  2 , some of the water which has settled on the windscreen  2  may not be collected by the wiper blade  14 . The wiper blade  14  may sweep over the water without it being scraped to the side of the windscreen  2 . This may be especially likely if the windscreen  2  is dirty or greasy, or if the material of the windscreen wiper blade  14  has begun to deteriorate. If the windscreen wipers are affected by this, water droplets and dirt may remain on the surface of the windscreen  2  and the vision of the driver may be impaired. 
         [0037]    Even when the wiper blades  14  are operating with optimal performance, it is still possible that some small water droplets will be left on the windscreen  2 . 
         [0038]    With reference to  FIG. 2 , the wiper blade  14 , according to an example of the present disclosure, is provided with one or more extraction openings  102 . The one or more openings  102  are provided on the wiper portion  14   a  of the wiper blade  14 . 
         [0039]    On the wiper blade depicted in  FIG. 2 , the one or more openings  102  comprise a single elongated slot which extends substantially along the full length of the wiper blade  14 . However, it is equally envisaged that the openings  102  could comprise a plurality of discrete openings along part or all of the length of the wiper blade  14 . 
         [0040]    In  FIG. 2 , the opening  102  is depicted on the edge of the wiper blade  14  which is in contact with the windscreen  2  and the opening is located between a leading surface  104  and a trailing surface  106  of the wiper portion  14   a.  Additionally or alternatively, the opening  102  may be provided on the leading surface  104  of the wiper blade  14 . Again, additionally or alternatively the opening  102  may be provided on the trailing surface  106  of the wiper blade  14 . The opening  102  may be positioned such that it is closest to any water on the windscreen  2  which has not been collected by the wiper blade as it sweeps across the windscreen. 
         [0041]    One or more internal channels  108  are provided within the wiper blade  14 . The opening  102  extends into the wiper blade  14  to meet the one or more channels  108 . The opening  102  is thereby in fluidic communication with the one or more channels  108 . 
         [0042]    In the example shown in  FIG. 2 , the one or more channels  108  comprise a single channel with a substantially circular cross section which extends along the full length of the wiper blade  14 . It is equally envisaged that the channel  108  may comprise a plurality of channels, and each of the channels may be connected in fluidic communication with a different subset of the openings  102 . For example, the one or more channels  108  could comprise two channels, the first of which is connected to a subset of openings  102  provided on the leading surface  104  of the wiper blade  14  and the second of which is connected to a subset of the openings  102  provided on the trailing surface  106  of the wiper blade. Alternatively, the channels  108  may extend different lengths along the wiper blade  14  and may connect to different subsets of the openings  102  separated along the length of the wiper blade  14 . Alternative configurations are also contemplated. 
         [0043]    In another example illustrated in  FIG. 3 , the leading surface  104 , and/or trailing surface  106  may be discontinuous or comprise one or more recesses, crenulations or serrations  105 , such that the leading and/or trailing surface does not contact the surface of the windscreen  2  continuously along its length. The serrations  105  may comprise triangular shaped cut outs from the leading and/or trailing surface of the wiper portion  14   a.  Alternatively the cut outs may be circular, semi-circular, square or any other shape. The serrations  105  may improve the flow of air, water, dirt and/or grease past the leading and/or trailing surfaces of the wiper portion  14   a  and may increase the amount of air, water, dirt and/or grease drawn through the one or more openings  102  and the one or more channels  108 . The serrations  105  may be substantially aligned with the one or more openings  102 . 
         [0044]    With reference to  FIG. 1 , the vehicle wiper assembly  10  further comprises a conduit  18 . The conduit  18  is coupled to the wiper blade  14  and is in fluidic communication with at least one of the one or more channels  108  at a first end of the conduit  18 . In the example shown in  FIG. 1  the conduit  18  comprises a flexible tube, however the conduit  18  may alternatively comprise a rigid tube or pipe, or may comprise a bore formed through a body of the vehicle wiper assembly  10 . 
         [0045]    The conduit  18  is connected, at a second end, to a suction pump  22 . The suction pump  22  is configured to pump air through the conduit  18 , thereby pumping air through the openings  102  and through the channels  18  within the wiper blade  14 . 
         [0046]    The suction pump  22  may comprise a mechanically or electrically driven suction pump. Alternatively, the suction pump  22  may comprise any other suitable pump. In the example shown in  FIG. 1 , the suction pump  22  comprises a ram air powered pump which is driven by a ram air source  4  provided on the vehicle, such as a ram air induction system (not shown), which may for example provide combustion air to an internal combustion engine of the vehicle. Ram air may be provided to the suction pump  22  via a ram air duct  26 . 
         [0047]    As described previously, during use of the windscreen wiper, it is likely that water will be present on the windscreen, at or around the openings  102 . Water is therefore entrained in the flow of air being pumped into the openings  102 . Any dirt or grease suspended in the water is also drawn in through the openings  102 . 
         [0048]    The action of drawing water and dirt and/or grease into the openings  102  during operation of the wiper system  10  reduces the amount of water and/or dirt and/or grease which remains on the windscreen following an operation of the wiper assembly  10 . The quality of vision that the driver has through the windscreen  2  is therefore improved relative to what it would have been with a conventional vehicle wiper assembly. 
         [0049]    A water separator  20  may be provided within the vehicle wiper assembly  10 . In the illustrated example, the water separator  20  is provided on the conduit  18  between its first and second ends, such that water and any suspended dirt and/or grease, which has been entrained in the flow of air through the conduit  18 , can be separated from the flow before it reaches the suction pump  22 . 
         [0050]    A drain pipe  24  is provided in the wiper assembly  10  which carries any separated water away from the water separator  20  to a fluid discharge outlet provided at a suitable drain point on the vehicle. 
         [0051]    Although in the arrangement shown in  FIG. 1 , the water separator  20  is provided on the conduit  18  upstream of the suction pump  22 , it is equally envisaged that the water separator may be provided downstream of the suction pump  22  and the suction pump may be configured to pump the mixture of air and water, dirt and/or grease. Alternatively, the suction pump  22  may comprise the separator  20 . 
         [0052]    The wiper assembly  10  may further comprise a controller  28 . The controller  28  may comprise one or more modules. In the illustrated example, the controller  28  is operatively connected to the wiper motor and actuator assembly  16  and the suction pump  22 . In use, the controller  28  or one or more modules of the controller coordinate the operation of the wiper motor and actuator assembly  16  and the suction pump  22  such that the suction pump  22  operates only during a period when water is likely to be present at or around the openings  102 , for example whilst the wiper blade  14  is being swept across the windscreen  2 . 
         [0053]    The wiper assembly  10  may further comprise a water sensor  30  and/or a dirt sensor  32 . In the illustrated example, the water sensor  30  and the dirt sensor  32  are operatively connected to the controller  28 . The controller  28  or one or more modules of the controller  28  may consider sensor readings from the water sensor  30  and/or the dirt sensor  32  when determining how to coordinate the operation of the wiper motor and actuator assembly  16  and the suction pump  22 . For example, if a high level of water is detected, the controller  28  or one or more modules of the controller may extend the duration over which the suction pump  22  is operating. 
         [0054]    Although the wiper assembly  10  has been described with reference to a vehicle windscreen  2 , it is equally envisaged that it could be applied to a tailgate window, headlight lens, wing mirror, or any other surface of a vehicle from which it is desirable to remove water and/or dirt and/or grease. 
         [0055]    It will be appreciated by those skilled in the art that although the wiper assembly  10  has been described by way of example, with reference to one or more exemplary examples, it is not limited to the disclosed examples and that alternative examples could be constructed without departing from the scope of the wiper assembly as defined by the appended claims.