Abstract:
A vehicle camera washing system is disclosed. In one embodiment, the system includes a housing configured for supporting a vehicle camera, a housing cover having an aperture for a lens of the vehicle camera, the housing cover removably positioned on a face of the housing, a circular groove positioned in the face of the housing, a first wiper anchor fixedly positioned in the groove, a second wiper anchor movably positioned in the groove, and elastic wiper extending from the first wiper anchor to the second wiper anchor.

Description:
BACKGROUND 
       [0001]    This application relates generally to the field of camera cleaning systems, and more particularly to systems and methods for cleaning external cameras mounted on a vehicle. 
         [0002]    A Reversing Video Device (RVD) may be mounted on vehicles, such as an automobile, to assist a driver of the vehicle to avoid objects and people in the path of the vehicle when the vehicle is driven, such as in reverse. RVD systems may include a camera, such as a Rear View Camera (RVC), mounted on the vehicle to capture video of the scene surrounding the vehicle, and a video display unit mounted in the driver&#39;s line of sight to allow the driver to view the display when driving the vehicle. 
         [0003]    Some mounting locations of a vehicle&#39;s camera, such as a rear view camera, may cause the camera&#39;s lens to collect dust, dirt, and debris, which may obscure the field of view of the camera. There exists a need, therefore, to provide a washing system that removes such dust, dirt, and debris to maintain the functionality of the camera or other externally facing device, such as a radar unit, while being easily accessible and maintainable by an owner of the vehicle. 
         [0004]    Some automobiles may have a rear window washing system, but adapting such systems to address the problem of a dirty rear view camera would require higher pressure fluid pumps to compensate for the additional pressure drop in the washer fluid line to reach the rear view camera. 
       SUMMARY 
       [0005]    A vehicle camera washing system is disclosed. In one embodiment, the system includes a housing configured for supporting a vehicle camera, a housing cover having an aperture for a lens of the vehicle camera, the housing cover removably positioned on a face of the housing, a circular groove positioned in the face of the housing, a first wiper anchor fixedly positioned in the groove, a second wiper anchor movably positioned in the groove, and an elastic wiper extending from the first wiper anchor to the second wiper anchor. 
         [0006]    The system may include a motor connected to the second wiper anchor. The motor may be configured to move the second wiper anchor along the groove from a first position to a second position. Movement of the second wiper anchor to the second position may stretch the wiping elements across the camera lens. The first position may be at a 3 o&#39;clock position on the face of the housing, and the second position may be at a 6 o&#39;clock position on the face of the housing. 
         [0007]    The motor may move the second wiper anchor in a counter-clockwise direction in the groove until the second position is reached, and then may move the second wiper anchor in a clockwise direction in the groove until the first position is reached, the wiper thereby being swept across the lens of the camera. The system may also include a fluid delivery system including a valve positioned on a periphery of the housing. The valve may be connected to a fluid tank by a conduit configured to convey a fluid from the fluid tank to the valve. The valve may be actuated to release the fluid onto the lens of the camera by movement of the second wiper anchor past the valve. The valve may be radially positioned at a 2 o&#39;clock position on the housing and a second valve may be radially positioned at a 10 o&#39;clock position on the housing. The wiper may include a plurality of wiping elements configured to sweep across the lens of the camera. 
         [0008]    Another embodiment of a vehicle camera washing system for a vehicle camera lens cover is disclosed. In this embodiment, the system includes a washer housing, a circular slot positioned in a face of the housing, a first wiper anchor fixedly positioned on the face of the housing, a second wiper anchor movably positioned in the slot, and a variable extension wiper extending from the first wiper anchor to the second wiper anchor, the wiper comprising a wiping element configured to sweep across the vehicle camera lens cover. 
         [0009]    The system may include a reciprocating motor connected to the second wiper anchor. The motor may be configured to move the second wiper anchor along the slot from a first position to a second position. Movement of the second wiper anchor to the second position may variably extend the wiping element across the vehicle camera lens cover. 
         [0010]    The reciprocating motor may move the second wiper anchor in a counter-clockwise direction in the slot until the second position is reached, and then may move the second wiper anchor in a clockwise direction in the slot until the first position is reached, the wiper thereby being swept across the camera lens cover. The system may include a rod pivotally connected on one end to an output shaft of the reciprocating motor and pivotally connected on an opposite end to the second wiper anchor. 
         [0011]    The first wiper anchor may include a valve connected to a fluid tank by a conduit configured to convey a fluid from the fluid tank to the valve. The valve may be configured to dispense the fluid onto the vehicle camera lens cover. The wiper may include at least one orifice positioned between the first wiper anchor and the second wiper anchor along the wiper. The at least one orifice may be connected to the valve for dispensing the fluid onto the vehicle camera lens cover. 
         [0012]    Another embodiment of a vehicle camera washing system for a vehicle camera lens cover is disclosed. In this embodiment, the system includes a driver gear, a first gear positioned adjacent to and driven by the driver gear, the first gear comprising a ring positioned around the lens cover, a wiper mount positioned adjacent to the first gear, and an elastic wiper pivotally attached to the wiper mount on one end and pivotally attached to a perimeter face of the first gear on an opposite end, the wiper configured to elastically extend and sweep across the lens cover upon rotational movement of the first gear by the driver gear. 
         [0013]    The system may include a motor connected to the driver gear. The motor may be configured to rotate the driver gear. The opposite end of the wiper may follow rotation of the first gear as the driver gear rotates in either a clockwise or counter-clockwise direction. The system may also include a controller connected to a computer processor. The controller may be coupled to the motor and configured to command rotation of the driver gear through a plurality of rotational angles and rotation cycles. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1A  illustrates a top view of a vehicle of the instant disclosure. 
           [0015]      FIG. 1B  illustrates a rear view of the vehicle shown in  FIG. 1A . 
           [0016]      FIG. 2  illustrates a block diagram of exemplary components of the vehicle shown in  FIG. 1A . 
           [0017]      FIG. 3  illustrates a block diagram of an exemplary computing device operatively connected to the vehicle shown in  FIG. 1A . 
           [0018]      FIG. 4A  illustrates a perspective view of an embodiment of a camera washing system of the instant disclosure with the housing cover removed and with the wiper shown in a first position. 
           [0019]      FIG. 4B  illustrates a perspective view of the camera washing system shown in  FIG. 4A  with the housing cover installed. 
           [0020]      FIG. 4C  illustrates a perspective view of another aspect of the camera washing system shown in  FIG. 4A  with the housing cover removed and with the wiper shown in a second one of a plurality of positions. 
           [0021]      FIG. 4D  illustrates a schematic view of another aspect of the camera washing system shown in  FIG. 4A  showing the wiper in one of a plurality of positions. 
           [0022]      FIG. 4E  illustrates a schematic view of another aspect of the camera washing system shown in  FIG. 4A  showing the wiper in a second one of a plurality of positions. 
           [0023]      FIG. 4F  illustrates a schematic view of another aspect of the camera washing system shown in  FIG. 4A  showing the wiper in a third one of a plurality of positions. 
           [0024]      FIG. 5A  illustrates a perspective view of another embodiment of a camera washing system of the instant disclosure with the housing cover removed. 
           [0025]      FIG. 5B  illustrates a perspective view of another aspect of the camera washing system shown in  FIG. 5A  with the wiper shown in another one of a plurality of positions. 
           [0026]      FIG. 5C  illustrates a partial detail perspective view of the camera washing system shown in  FIG. 5B . 
           [0027]      FIG. 5D  illustrates a perspective view of another aspect of the camera washing system shown in  FIG. 5A . 
           [0028]      FIG. 6A  illustrates an exploded perspective view of another embodiment of a camera washing system of the instant disclosure. 
           [0029]      FIG. 6B  illustrates a perspective view of the camera washing system shown in  FIG. 6A . 
           [0030]      FIG. 6C  illustrates a partial detail perspective view of the camera washing system shown in  FIG. 6A  showing the wiper in a first one of a plurality of positions. 
           [0031]      FIG. 6D  illustrates a partial detail perspective view of the camera washing system shown in  FIG. 6A  showing the wiper in a second one of a plurality of positions. 
           [0032]      FIG. 6E  illustrates a partial detail perspective view of the camera washing system shown in  FIG. 6A  showing the wiper in a third one of a plurality of positions. 
           [0033]      FIG. 6F  illustrates a partial detail perspective view of the camera washing system shown in  FIG. 6A  showing the wiper in a fourth one of a plurality of positions. 
           [0034]      FIG. 6G  illustrates a partial detail perspective view of the camera washing system shown in  FIG. 6A  showing the wiper in a fifth one of a plurality of positions. 
       
    
    
     DETAILED DESCRIPTION 
       [0035]    Although the figures and the instant disclosure describe one or more embodiments of a camera washing system, one of ordinary skill in the art would appreciate that the teachings of the instant disclosure would not be limited to these embodiments. 
         [0036]    Turning now to the drawings wherein like reference numerals refer to like elements, there are shown exemplary embodiments and methods of a washing system for a vehicle camera or other device that may collect dust, dirt, and/or debris for which cleaning may be useful. 
         [0037]      FIGS. 1A-1B  show vehicle  100  in accordance with one embodiment of the instant disclosure. In this embodiment, vehicle  100  is an automobile, though in other embodiments vehicle  100  may be any suitable vehicle (such as a truck, a watercraft, or an aircraft). Vehicle  100  may be a gasoline powered vehicle, a hybrid vehicle, an electric vehicle, a fuel cell vehicle, or any other type of suitable vehicle. Vehicle  100  may include standard features, such as a dashboard, adjustable seats, one or more batteries, an engine or motor, a transmission, an HVAC system including a compressor and electronic expansion valve, a windshield and/or one or more windows, doors, a rear view mirror, a right side view mirror, a left side view mirror, seatbelts, airbags, wheels, and tires. 
         [0038]    As shown in  FIGS. 1A-1B and 2 , vehicle  100  may include sensors  102 , which may be arranged in and around the vehicle in a suitable fashion. Sensors  102  can all be the same or they can vary from one to the next. Sensors  102  may include many sensors or only a single sensor. 
         [0039]    Certain of the sensors  102  may be configured to obtain data about the environment surrounding the vehicle (e.g., position sensors or weather sensors), as indicated by the dashed line in  FIG. 1A , while others obtain data about components of the vehicle itself (e.g., gas level sensors or oil pressure sensors). The sensors  102  may be configured to transmit the data they obtain to one or more controllers of the vehicle  100 , such as to controller  210  (described below), for further processing. The sensors  102  may include any suitable sensor or sensors such as, but not limited to: (1) infrared sensors; (2) visual sensors (such as cameras); (3) ultrasonic sensors; (4) RADAR; (5) LIDAR; (6) laser-scan sensors; (7) inertial sensors (for example, an inertial measurement unit); (8) wheel speed sensors; (9) road condition sensors (to directly measure certain road conditions); (10) rain sensors; (11) suspension height sensors; (12) steering wheel angle sensors; (13) steering torque sensors; (14) brake pressure sensors; (15) tire pressure sensors; or (16) vehicle location or navigation sensors (such as a Global Positioning System). Sensors  102  may include gear sensors configured to detect gear engagement of the vehicle&#39;s transmission, accelerometers configured to detect vehicle acceleration, speed sensors to detect vehicle speed, wheel speed, and/or steering wheel speed, torque sensors to detect engine or motor output torque, driveline torque, and/or wheel torque, and position sensors to detect steering wheel angular position, brake pedal position, and/or mirror position. Some sensors  102  may be mounted inside the passenger compartment of vehicle  100 , around the exterior of the vehicle, or in the engine compartment of vehicle  100 . At least one sensor  102  may be used to identify the vehicle&#39;s driver via facial recognition, speech recognition, or communication with a device, such as a vehicle key or mobile phone personal to the driver. 
         [0040]    Sensors  102  may have an OFF state and various ON states. Vehicle  100 , or a device operatively connected to the vehicle, may be configured to control the states or activity of the sensors. It should be appreciated that the term “internal sensors” includes all sensors mounted to the vehicle, including sensors that are mounted to an exterior of vehicle  100 . 
         [0041]    As shown in  FIG. 2 , in one embodiment, vehicle  100  includes a vehicle data bus  202  operatively coupled to sensors  102 , vehicle drive devices  206 , memory or data storage  208 , a processor or controller  210 , a user interface  212 , communication devices  214 , and a disk drive  216 . 
         [0042]    The processor or controller  210  may be any suitable processing device or set of processing devices such as, but not limited to: a microprocessor, a microcontroller-based platform, a suitable integrated circuit, or one or more application-specific integrated circuits (ASICs). 
         [0043]    The memory  208  may be volatile memory (e.g., RAM, which can include non-volatile RAM, magnetic RAM, ferroelectric RAM, and any other suitable forms); non-volatile memory (e.g., disk memory, FLASH memory, EPROMs, EEPROMs, memristor-based non-volatile solid-state memory, etc.); unalterable memory (e.g., EPROMs); read-only memory; a hard drive; a solid state hard drive; or a physical disk such as a DVD. In an embodiment, the memory includes multiple kinds of memory, particularly volatile memory add non-volatile memory. 
         [0044]    The communication devices  214  may include a wired or wireless network interface to enable communication with an external network. The external network may be a collection of one or more networks, including standards-based networks (e.g., 2G, 3G, 4G, Universal Mobile Telecommunications Autonomous valet parking system (UMTS), GSM® Association, Long Term Evolution (LTE)™, or more); WMAX; Bluetooth; near field communication (NFC); WFi (including 802.11 a/b/g/n/ac or others); WiMAX; Global Positioning System (GPS) networks; and others available at the time of the filing of this application or that may be developed in the future. Further, the external network(s) may be a public network, such as the Internet; a private network, such as an intranet; or combinations thereof, and may utilize a variety of networking protocols now available or later developed including, but not limited to, TCP/IP-based networking protocols. The communication devices  214  may also include a wired or wireless interface to enable direct communication with an electronic device, such as a USB or Bluetooth interface. 
         [0045]    The user interface  212  may include any suitable input and output devices. The input devices enable a driver or a passenger of vehicle  100  to input modifications or updates to information shown in, for example, a vehicle display. The input devices may include, for instance, a control knob, an instrument panel, a keyboard, a scanner, a digital camera for image capture and/or visual command recognition, a touch screen, an audio input device (e.g., cabin microphone), buttons, a mouse, or a touchpad. The output devices may include instrument cluster outputs (e.g., dials, lighting devices), actuators, a display (e.g., a liquid crystal display (“LCD”), an organic light emitting diode (“OLED”), a flat panel display, a solid state display, a cathode ray tube (“CRT”), or a heads-up display), and speakers. It should be appreciated that the term pressing a button or feature also includes pressing or activating a virtual button or feature, such as using a mouse to click on an item on a display, or pressing a virtual button on a touch screen. 
         [0046]    The disk drive  216  is configured to receive a computer readable medium. In certain embodiments, the disk drive  216  receives the computer-readable medium on which one or more sets of instructions, such as the software for operating system  400  described below. The instructions may embody one or more of the methods or logic as described herein. In a particular embodiment, the instructions may reside completely, or at least partially, within any one or more of the main memory  208 , the computer readable medium, and/or within the processor  210  during execution of the instructions. 
         [0047]    The term “computer-readable medium” should be understood to include a single medium or multiple media, such as a centralized or distributed database, and/or associated caches and servers that store one or more sets of instructions. The term “computer-readable medium” also includes any tangible medium that is capable of storing, encoding or carrying a set of instructions for execution by a processor or that cause a system to perform any one or more of the methods or operations disclosed herein. 
         [0048]    In one embodiment, the vehicle  100  includes a one or more computer programs or subprograms stored in the memory  208 . When executed by the processor, the one or more computer programs or subprograms generate or select instructions for other elements of the vehicle to perform. In various embodiments, the one or more computer programs or subprograms are configured to direct instructions to the user interface  212 , the communication devices  214 , the vehicle drive  206 , the sensors  102 , the processor  210 , and any other component operatively connected to the vehicle data bus  202 . It should be appreciated that vehicle  100  may be fully autonomous or partially autonomous. 
         [0049]    In various embodiments, a computing device  105  is operatively connected to the vehicle  100  via any suitable data connection such as WFi, Bluetooth, USB, or a cellular data connection. In one embodiment, shown in  FIG. 3 , the computing device  105  includes a data bus  302 , operatively coupled to sensors  306 , components  316 , memory or data storage  308 , a processor or controller  310 , a user interface  312 , and communication devices  314 . It should be appreciated that the features of the computing device  105  may be similar to the features of the vehicle  100  as described above. For example, the communication devices  314  of the computing device  105  may operate similar to the communication devices  214  of the vehicle  100 . The same applies to the user interface  312 , the sensors  306 , the data storage  308 , the processor  310 , and the disk drive  318 . In various embodiments, the computing device  105  is a mobile phone or a server. 
         [0050]    Turning to  FIGS. 4A-4F , there is shown a camera washing system  400  to clean camera lens or cover  405  of a vehicle camera. In one embodiment, camera washing system  400  includes housing  410 , housing cover  412 , first wiper anchor  420 , second wiper anchor  422 , slot or track  430 , and wiper  440 . In some embodiments, camera washing system  400  also includes fluid delivery system  450  comprising washer fluid tank  460 , washer fluid  462 , first conduit  470 , second conduit  472  and one or more valves  480 . 
         [0051]    Housing cover  412  includes an aperture  414 , which permits an unobstructed view for the optics of camera  402  to capture the scene in the vicinity of vehicle  100 . Housing cover  412  is configured to be detachably connected to housing  410  to easily remove and replace worn components of camera washing system  400 . 
         [0052]    Wiper  440  comprises an elastic material that extends from first wiper anchor  420  to second wiper anchor  422 . In this embodiment, wiper  440  includes first wiper band  442  and second wiper band  444 . Wiper  440  may comprise a rubber or any resilient material. First wiper anchor  420  is configured to lie in a fixed position in or near track  430 . Second wiper anchor  422  is configured to be moveable along track  430  from a first, starting position to a second, ending position. As shown in the embodiments of  FIGS. 4A  and  FIGS. 4C , track  430  can be circular in shape. As will be discussed in greater detail below, the movement of second wiper anchor  422  along track  430  causes wiper  440  to stretch across and swipe across camera lens  405  to push away dust, dirt, debris, snow, and water, etc. away from the surface of camera lens  405 . 
         [0053]    As shown in  FIG. 4C , camera washing system  400  may include fluid delivery system  450 , which may include first conduit  470  and second conduit  472 , each connecting washer tank  460  to housing  410  via one or more valves  480 . In the embodiment of  FIG. 4C , a valve  480  is positioned at approximately the 10 o&#39;clock position of housing  410  and another valve  480  is positioned at approximately the 2 o&#39;clock position of housing  410 . As shown in  FIG. 4C , as second wiper anchor  422  traverses along track  430  in either a counterclockwise or clockwise motion, second wiper anchor  422  traverses past valve  480 , which causes valve  480  to open and release fluid  462  from washer tank  460 . Fluid  462  may enhance the cleaning of camera lens  405  as wiper  440  sweeps across camera lens  405 . 
         [0054]    The one or more valves may be positioned at any position depending on the orientation of housing  410  to gravity. For example, with valves  480  positioned at the 10 o&#39;clock position and the 2 o&#39;clock position, fluid  462  from washer tank  460  may be conveyed via gravity to valves  480  via first conduit  470  and second conduit  472  and thereafter dispensed onto camera lens  405 . Fluid  462  dispensed from valves  480  may flow across camera lens  405  due to gravity and also be wiped across camera lens  405  due to movement of wiper  440  across camera lens  405 . The one or move valves  480  may include biasing spring  481  and valve closure member  482 . Spring  481  may bias valve closure member  482  in the valve closed position until second wiper anchor  422  is commanded to traverse past closure member  482 , which motion deflects valve closure member  482  into the valve open position to release fluid  462  from fluid delivery system  450 . In other embodiments, the one or more valves  480  may be any mechanical or electro-mechanical valve including a solenoid-controlled valve or proportioning valve. In some embodiments, a controller having a timer may time the opening of the one or more valves  480  and the valve  480  may be electrically opened and closed. 
         [0055]    Turning to  FIGS. 4D-4F , there is shown one method of moving second wiper anchor  422  along track  430 . As shown, camera washing system  400  may include motor  485  and rod  486 . Motor  485  may be configured as a reciprocating motor. Rod  486  may be configured as a rod, an I-beam, or any other geometry to communicate motion from motor  485  to second wiper anchor  422 . Rod  486  may be pivotally connected to pivot  487  on one end, and pivotally connected to second wiper anchor  422  on the other end. Pivot  487  may be connected to output shaft  488  of motor  485 . When motor  485  is commanded to activate, output shaft  488  may translate fore and aft thereby moving rod  486 . With second wiper anchor  422  being constrained to move along track  430  while being connected to rod  486 , as output shaft  488  is pulled aft by motor  485 , second wiper anchor  422  is caused to traverse counter-clockwise along track  430  from the first, starting position (best shown in  FIG. 4A ) to the second, ending position (best shown in  FIG. 4E ). 
         [0056]    Motor  485  may be commanded to operate continuously, which forces second wiper anchor  422  clockwise along track  430  until the first, starting position is reached, and then back again in a counter-clockwise direction to the second, ending position. In this way, multiple passes of wiper  440  may be made across camera lens  405  in a single command cycle of motor  485 . In addition, as discussed above, as second wiper anchor  422  passes each valve  480  in sequence, washer fluid  462  is dispensed, which may be wiped across camera lens  405  by wiper  440 . 
         [0057]    Another embodiment of a camera washing system is shown in  FIGS. 5A-5D . In this embodiment, camera washing system  500  includes all of the same features and operates in the same way as camera washing system  400  except that the wiper and washer fluid delivery system is different. Specifically, camera washing system  500  includes housing  510 , housing cover  512  (not shown), first wiper anchor  520 , second wiper anchor  522 , slot or track  530 , and wiper  540 . Camera washing system  500  also includes fluid delivery system  550  comprising washer fluid tank  560 , washer fluid  562 , conduit  570 , and one or more valves  580 . 
         [0058]    Wiper  540  comprises a tubular structure that extends from first wiper anchor  520  to second wiper anchor  522 . First wiper anchor  520  is configured to lie in a fixed position in or near track  530 . Second wiper anchor  522  is configured to be moveable along track  530  from a first, starting position to a second, ending position. Track  530  can be circular in shape. Similar to camera washing system  400 , movement of second wiper anchor  522  along track  530  causes wiper  540  to stretch and/or telescope across and swipe across camera lens  505  to push away dust, dirt, debris, snow, and water, etc. away from the surface of camera lens  505 . 
         [0059]    As shown in  FIG. 5D , camera washing system  500  may include fluid delivery system  550 , which may include conduit  570  connecting washer tank  560  to housing  510  via valve  580  positioned in first wiper anchor  520 . In this embodiment, wiper  540  includes one or more fluid orifices  545  where wiper  540  acts as a conduit for fluid  562 . 
         [0060]    In this embodiment, fluid  562  from washer tank  560  may be conveyed via gravity via conduit  570  to first wiper anchor  520  having valve  580 . When valve  580  opens, fluid  562  is conveyed inside the conduit formed by wiper  540  to the one or more fluid orifices  545  and thereafter dispensed onto camera lens  505 . Fluid  462  dispensed from valves  480  may flow across camera lens  405  due to gravity and also be wiped across camera lens  405  due to movement of wiper  440  across camera lens  405 . 
         [0061]    Valve  580  may be any mechanical or electro-mechanical valve including a solenoid-controlled valve or proportioning valve. In some embodiments, a controller having a timer may time the opening of valve  580  and valve  580  may be electrically opened and closed to allow fluid  562  to be dispensed. 
         [0062]    Another embodiment of a camera washing system for retrofitting an existing vehicle camera system is shown in  FIGS. 6A-6G . In this embodiment, camera washing system  600  includes driver gear  610 , gear  615 , wiper  640 , and wiper mount  660 . Driver gear  610  is connected to gear  615  via gear teeth  620 , 622 . In one embodiment, wiper  640  comprises an elastic material. Wiper  440  may comprise a rubber or any resilient material. In another embodiment, wiper  640  is configured to extend from a first position to a second position. 
         [0063]    One end  630  of wiper  640  is attached to pivot  645  and the other end  632  of wiper  640  is attached along a perimeter of gear  615 . Driver gear  610  is connected to a motor (not shown). As the driver gear  610  is commanded to rotate via the motor, gear  615  turns correspondingly. End  632  of wiper  640  follows the rotation of gear  615  as gear  615  rotates in either a clockwise or counter-clockwise direction depending on the direction of rotation of driver gear  610 . In one embodiment, wiper  640  extends from a first length when end  632  is at a first, starting position (see, e.g.,  FIG. 6C ) to a second length when end  632  is positioned opposite pivot  645  on the other side of gear  615 . The motor may continue to turn until wiper  640  reaches the end of its stroke, as shown in  FIG. 6F , at which point the motor may be commanded to reverse and cause gear  615  to rotate in the counter-clockwise direction to return to the stroke starting position, as shown in  FIG. 6F . In other embodiments, gear  615  may be caused to make 360 degree revolutions. 
         [0064]    While specific embodiments have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the disclosure herein is meant to be illustrative only and not limiting as to its scope and should be given the full breadth of the appended claims and any equivalents thereof.