Patent Publication Number: US-2015059105-A1

Title: Shields or seals to shelter an area underneath a dock leveler

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This patent arises as a continuation of U.S. patent application Ser. No. 14/017,069, filed on Sep. 3, 2013, entitled “Shields or Seals to Shelter an Area Underneath a Dock Leveler”, which is hereby incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE DISCLOSURE 
     This patent generally pertains to dock levelers at vehicle loading docks and, more specifically, to shield or seals to shelter an area underneath a dock leveler. 
     BACKGROUND 
     A typical loading dock of a building includes an exterior doorway with an elevated platform for loading and unloading vehicles, such as trucks and trailers. To compensate for height differences between the loading dock platform and an adjacent bed of a truck or trailer, many loading docks have a dock leveler. A typical dock leveler includes a deck or ramp that is pivotally hinged along its back edge to vary the height of its front edge. A retractable extension plate or lip pivots or translates outward from the deck&#39;s front edge to span a gap between a rear of the truck bed and the front edge of the deck. The deck and lip provide a bridge between the dock&#39;s platform and the vehicle&#39;s bed so that personnel and material handling equipment can readily move on and off the vehicle during loading and unloading operations. 
     To help shield against weather while a vehicle is being serviced at the dock, a seal is usually installed around the perimeter of the doorway. Such seals are typically installed along upper and side edges of the doorway to help seal any air gaps that may otherwise exist between a face of the building and the rear of the vehicle. The dock leveler lip, when resting upon the rear of the vehicle, may provide a seal to a portion of a lower end of the doorway. 
     The area or pit underneath a dock leveler&#39;s deck, however, is usually exposed to outside air. This can create problems, particularly when there is a significant temperature differential between the indoor and outdoor air. Warm outside air, for example, may condense underneath a relatively cool deck of a dock leveler used in a cold storage warehouse. The condensation can promote corrosion of various parts of the dock leveler. Conversely, a heated building during the winter may lose a significant amount of heat by thermal conduction through the deck, as cold outside air cools the deck from underneath. Moreover, when the indoor air is relatively warm while the deck is cooled by outside air, condensation can form on top of the deck. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side cross-sectional view of an example dock leveler constructed in accordance with the teachings disclosed herein, wherein the dock leveler&#39;s deck is shown in a cross-traffic position and an adjacent vehicle is shown in phantom lines. 
         FIG. 2  is a side cross-sectional view similar to  FIG. 1  but showing a lip of the example dock leveler at an extended position. 
         FIG. 3  is a right end view of  FIG. 1 . 
         FIG. 4  is a side cross-sectional view similar to  FIG. 1  but showing the example deck in a raised position and the lip in the extended position. 
         FIG. 5  is a side cross-sectional view similar to  FIG. 1  but showing the example deck in a lowered position. 
         FIG. 6  is a side cross-sectional view similar to  FIG. 5  but showing the example lip in a partially extended position. 
         FIG. 7  is a side cross-sectional view similar to  FIG. 1  but showing another example dock leveler constructed in accordance with the teachings disclosed herein, wherein the deck is shown in the cross-traffic position and the lip is in the retracted position. 
         FIG. 8  is a side cross-sectional view similar to  FIG. 7  but showing the example deck in a raised position and the example lip in an extended position. 
         FIG. 9  is a side cross-sectional view similar to  FIG. 8  but showing the example deck in a lowered position and the example lip in a partially extended position. 
         FIG. 10  is a side cross-sectional view similar to  FIG. 1  but showing another example dock leveler constructed in accordance with the teachings disclosed herein, wherein the deck is shown in the cross-traffic position and the lip is in the retracted position. 
         FIG. 11  is a side cross-sectional view similar to  FIG. 10  but showing the example deck in a raised position and the example lip in an extended position. 
         FIG. 12  is a side cross-sectional view similar to  FIG. 11  but showing the example deck in a lowered position and the example lip in a partially extended position. 
         FIG. 13  is a side cross-sectional view similar to  FIG. 1  but showing another example dock leveler constructed in accordance with the teachings disclosed herein, wherein the deck is shown in the cross-traffic position and the lip is in the retracted position. 
         FIG. 14  is a side cross-sectional view similar to  FIG. 13  but showing the example deck in a raised position and the example lip in an extended position. 
         FIG. 15  is a side cross-sectional view similar to  FIG. 14  but showing the example deck in a lowered position and the example lip in a partially extended position. 
         FIG. 16  is a side cross-sectional view similar to  FIG. 1  but showing another example dock leveler constructed in accordance with the teachings disclosed herein, wherein the deck is shown in the cross-traffic position and the lip is in the retracted position. 
         FIG. 17  is a side cross-sectional view similar to  FIG. 16  but showing the example deck in a raised position and the example lip in an extended position. 
         FIG. 18  is a side cross-sectional view similar to  FIG. 17  but showing the example deck in a lowered position and the example lip in a partially extended position. 
         FIG. 19  is a side cross-sectional view similar to  FIG. 1  but showing another example dock leveler constructed in accordance with the teachings disclosed herein, wherein the deck is shown in the cross-traffic position and the lip is in the retracted position. 
         FIG. 20  is a side cross-sectional view similar to  FIG. 19  but showing the example deck in a raised position and the example lip in an extended position. 
         FIG. 21  is a right end view of  FIG. 19 . 
         FIG. 22  is a side cross-sectional view similar to  FIG. 1  but showing another example dock leveler constructed in accordance with the teachings disclosed herein, wherein the deck is shown in the cross-traffic position and the lip is in the retracted position. 
         FIG. 23  is a side cross-sectional view similar to  FIG. 22  but showing the example deck in a raised position and the example lip in an extended position. 
         FIG. 24  is a right end view of  FIG. 22 . 
         FIG. 25  is a side cross-sectional view similar to  FIG. 1  but showing another example dock leveler constructed in accordance with the teachings disclosed herein. A deck of the example dock leveler is shown in a cross-traffic position and a lip of the example dock leveler is shown in the retracted position. 
         FIG. 26  is a side cross-sectional view similar to  FIG. 25  but showing the example deck in a raised position and showing the example lip in an extended position. 
         FIG. 27  is a side cross-sectional view similar to  FIG. 26  but showing the example deck in a lowered position and the example lip in a partially extended position. 
         FIG. 28  is a side cross-sectional view similar to  FIG. 1  but showing another example dock leveler constructed in accordance with the teachings disclosed herein, wherein the deck is shown in the cross-traffic position and the lip is in the retracted position. 
         FIG. 29  is a side cross-sectional view similar to  FIG. 28  but showing the example deck in a raised position and the example lip in an extended position. 
         FIG. 30  is a side cross-sectional view similar to  FIG. 29  but showing the example deck in a lowered position and the example lip in a partially extended position. 
         FIG. 31  is a side cross-sectional view similar to  FIG. 1  but showing another example dock leveler constructed in accordance with the teachings disclosed herein, wherein the deck is shown in the cross-traffic position and the lip is in the retracted position. 
         FIG. 32  is a side cross-sectional view similar to  FIG. 31  but showing the example deck in a raised position and the example lip in an extended position. 
         FIG. 33  is a side cross-sectional view similar to  FIG. 32  but showing the example deck in a lowered position and the example lip in a partially extended position. 
         FIG. 34  is a side cross-sectional view similar to  FIG. 1  but showing another example dock leveler constructed in accordance with the teachings disclosed herein, wherein the deck is shown in the cross-traffic position and the lip is in the retracted position. 
         FIG. 35  is a side cross-sectional view similar to  FIG. 34  but showing the example deck in a raised position and the example lip in an extended position. 
         FIG. 36  is a side cross-sectional view similar to  FIG. 35  but showing the example deck in a lowered position with the example lip in a partially extended position. 
         FIG. 37  is a side cross-sectional view similar to  FIG. 1  but showing another example dock leveler constructed in accordance with the teachings disclosed herein, wherein the deck is shown in the cross-traffic position and the lip is in the retracted position. 
         FIG. 38  is a side cross-sectional view similar to  FIG. 37  but showing the example deck in a raised position and the example lip in an extended position. 
         FIG. 39  is a side cross-sectional view similar to  FIG. 38  but showing the example deck in a lowered position and the example lip in a partially extended position. 
         FIG. 40  is an exploded perspective view plus a right end view of example dock leveler in accordance with the teachings disclosed herein. 
         FIG. 41  is a side cross-sectional view similar to  FIG. 1  but showing another example dock leveler constructed in accordance with the teachings disclosed herein, wherein the deck is shown in the cross-traffic position and the lip is in the retracted position. 
         FIG. 42  is a side cross-sectional view similar to  FIG. 41  but showing the example deck in a raised position and the example lip in an extended position. 
         FIG. 43  is a side cross-sectional view similar to  FIG. 42  but showing the example deck in a lowered position and the example lip in a partially extended position. 
     
    
    
     DETAILED DESCRIPTION 
     Example weather shields disclosed herein are configured for use with dock levelers having deck-support legs that support a deck at a cross-traffic position (e.g., a substantially horizontal or level position). In particular, the deck-supporting legs of some such example dock levelers disclosed herein protrude downward from an underside of the deck and move along with a lip of the deck and may cause areas underneath the deck that may be difficult to seal. Some example weather shields disclosed herein shift or move with the deck and/or lip in a manner that maintains an effective seal regardless of the positions of the deck, lip and/or deck-supporting legs. For loading docks with an open area underneath a dock leveler that accommodates a rear liftgate of a truck, some example weather shields disclosed herein include means to prevent the example shield from obstructing the open area underneath the dock leveler. Some example weather shields disclosed herein include removable segments to enable adjustability of a dimensional width of the example weather shields disclosed herein. 
       FIGS. 1-6  show an example loading dock  10  with an example dock leveler  12  comprising a frame  14  supporting a vertically adjustable deck  16 , which in turn carries a lip structure  18  that can extend and retract relative to deck  16 . The term, “vertically adjustable deck” means that the elevation of at least a portion of the deck can be changed. Deck  16  and lip structure  18  are shown in various positions for loading and unloading cargo of a vehicle  20  (e.g., a truck or trailer). Dock leveler  12  is installed within a pit  22  defined by a wall  24  that extends from a ground surface  26  to a platform  28  of dock  10 . Some examples of wall  24  are substantially vertical and/or flat to provide a substantially uniform pit width. Some examples of wall  24  are inclined, stepped and/or irregular to provide a non-uniform pit width. In the illustrated examples, ground surface  26  lies generally flush with a driveway  30  upon which vehicle  20  is parked. A building wall  32 , defining a dock face  34 , separates a building&#39;s interior  36  from an outdoor area  38 . In some examples, a door selectively opens and closes across a doorway  41  through wall  32 . For reference, arrow  42  of  FIG. 1  represents a forward direction relative to building wall  32 , and arrow  44  of  FIG. 3  represents a horizontal or lateral direction relative to building wall  32 , where forward direction  42  is perpendicular to lateral direction  44 . Dock face  34  generally faces in forward direction  42 . 
     To illustrate an undesirable air gap  46  ( FIG. 4 ) that can exist between deck  16  and frame  14 ,  FIGS. 1-6  show dock leveler  12  without a weather shield that, if installed in the area of gap  46 , could block outside extreme temperature air and/or other elements from entering or flowing through gap  46  and circulating underneath deck  16 .  FIGS. 7-36  show various example weather shields or seals constructed in accordance with the teachings disclosed herein to seal gap  46 , and  FIG. 37  illustrates example methods for producing and using the example weather shields or seals disclosed herein. In the present detailed description, dock leveler  12  without a weather shield is described first, example dock levelers with example weather shields are described next, and a description of example dock leveler methods is after that. 
     Referring first to the example shown in  FIGS. 1-6 , deck  16  includes a plurality of joists  48  supporting a deck plate  50  that extends from a rear edge  52  to a front edge  54 . A hinge  56  connecting rear edge  52  to frame  14 , wall  24  and/or platform  28  enables a deck actuator (e.g., a hydraulic cylinder, a linear motor, a pneumatic cylinder, a bellows, a spring, a linkage, and/or various combinations thereof, etc.) to pivot deck  16  about rear edge  52  to adjustably raise and lower front edge  54 . This allows the deck&#39;s front edge  54  to be generally aligned to a rear edge  58  of a truck or trailer bed of vehicle  20 . To eliminate potentially hazardous pinch points between platform  28  and the deck&#39;s lateral edges  60  when deck  16  is raised above platform  28 , deck  16  of the illustrated example includes toe guards  62  having metal plates that are fixed to, extending downward from, and flanking deck plate  50 . Toe guards  62  slide alongside wall  24  as deck  16  moves to various positions. 
     The various positions of deck  16  include a raised position ( FIG. 4 ), a lowered position ( FIGS. 5 and 6 ) and a cross-traffic position ( FIGS. 1-3 ). In the raised position, the front edge  54  of the deck  16  is at a predetermined or specified raised elevation (e.g., a maximum or fully raised position). In the lowered position, the front edge  54  is at a predetermined or specified lowered elevation (e.g., a minimum or fully lowered position). In the cross-traffic position, the front edge  54  of the deck  16  is at a predetermined or specified intermediate elevation between the raised and lowered positions or elevations. In some examples, deck plate  50  is substantially flush with platform  28  when deck  16  is in the cross-traffic position. 
     Still referring to  FIGS. 1-6 , lip structure  18  includes a plurality of joists  64 , a header plate  66  at the front end of joists  64 , a lip plate  68  overlying joists  64 , at least one deck-supporting foot  70  extending downward from joists  64 , and a plurality of gussets  72  attached to the front of header plate  66  and to the underside of lip plate  68 . A lip actuator (e.g., a hydraulic cylinder, a linear motor, a pneumatic cylinder, a bellows, a spring, a linkage, and/or various combinations thereof, etc.) moves lip structure  18  between a retracted position ( FIG. 1 ) and various extended positions (FIGS.  2  and  4 - 6 ). In the illustrated example, lip structure  18  moves between the retracted and extended positions by translating relative to deck  16 . In some examples lip joists  64  slide along deck joists  48 . Some example lip structures pivot between retracted and extended positions. 
     To support deck  16 , frame  14  includes various structural members such as, for example, a beam  74  and a front beam  76 . To solidly support deck  16  at the cross-traffic position without having to rely on the deck actuator to hold it there, deck-supporting foot  70  of the illustrated example engages and rests upon a landing pad or deck-supporting surface  78  of front beam  76 .  FIGS. 1 and 3  show deck-supporting foot  70  engaging deck-supporting surface  78  to support deck  16  in the cross-traffic position. In some examples, deck-supporting foot  70  is vertically elongate to allow deck  16  to move between the cross-traffic position (e.g., of  FIG. 1 ) and the lowered position (e.g., of  FIG. 6 ). 
     In the illustrated examples, at least portions of frame  14  are elevated above ground surface  26  to create an open space  80  for accommodating a protuberance  82  (e.g., a liftgate) that might extend from some examples of vehicle  20 . In some examples, as indicated by phantom line  24 ′ of  FIG. 3 , the width of open space  80  is greater or wider than other the width of other areas of pit  22 . To help shield the underside of deck  16  from outdoor air that enters open space  80 , some examples of dock leveler  12  include a bottom panel  84  under deck  16  adjacent frame  14 . In some examples, bottom panel  84  is thermally insulated. Some examples of bottom panel  84  are attached to frame  14 . Some examples of bottom panel  84  are attached to wall  24 . In some examples, a front edge  86  of bottom panel  84  is adjacent to front beam  76 . In some examples, front edge  86  is adjacent to dock face  34  (see  FIG. 7 ). In some examples, front edge  86  is positioned at an intermediate location between front beam  76  and dock face  34 . 
       FIGS. 7-9  show an example dock leveler  12   a  that includes an example weather shield  88 .  FIGS. 7 ,  8  and  9  correspond to  FIGS. 1 ,  4  and  6 , respectively. For example,  FIG. 7  shows deck  16  at a cross-traffic position and lip structure  18  at a retracted position.  FIG. 8  shows deck  16  at a raised position and lip structure  18  at an extended position (e.g., a fully extended position).  FIG. 9  shows deck  16  at a lowered position and lip structure  18  at another extended position (e.g., a not fully extended position). 
     In this example, weather shield  88  includes a flexible sheet of material having an upper end  90  attached to header plate  66 , a lower end  92  attached to front beam  76 , and an intermediate section  94  that tends to droop or sag when dock leveler  12   a  is positioned as shown in  FIGS. 7  and  9 . The drooping section of weather shield  88  allows deck-supporting foot  70  to descend below deck-supporting surface  78  as shown, for example, in  FIG. 9 . In some examples, lower end  92  is positioned, located and/or attached to the lower end of front beam  76  adjacent to bottom panel  84 ′. In some examples, lower end  92  is positioned, located and/or attached to the upper end of front beam  76  near deck-supporting surface  78 . Weather shield  88  of the illustrated example has a lateral width extending across substantially a full width  96  (e.g., the width shown in  FIG. 3 ) of pit  22  to create or provide a sliding seal against wall  24  and/or against toe guard  62 . The term, “full width” refers to the width of pit  22  in the area above the bottom panel (e.g., bottom panels  84 ,  84 ′ and  84 ″). As lip structure  18  extends from the retracted position ( FIG. 7 ) to an extended position ( FIGS. 8 and 9 ), lip structure  18  carries or causes an upper end  90  of the weather shield  88  to move while deck-supporting foot  70  moves between a position behind or rearward of the lower end  92  of the weather shield  88  and a position forward or in front of lower end  92  of the weather shield  88 . In this example, front edge  86  of bottom panel  84 ′ is proximate dock face  34  to prevent the intermediate section  94  of weather shield  88  from drooping into open area  80 . In other words, as shown in  FIGS. 7 and 9 , at least a portion of the intermediate section  94  of the example weather shield  88  may rest on the bottom panel  84 ′. Not only can such drooping interfere with the liftgate  82  of vehicle  20 , but if the open space  80  is extra wide and extends to phantom line  24 ′ of  FIG. 3 , some shields might not be wide enough to seal against the side walls of the pit  22  in the area below the bottom panel (e.g., below bottom panel  84 ,  84 ′ or  84 ″). 
     Example materials and construction of weather shield  88  include, but are not limited to, vinyl coated fabric, non-insulated sheet, insulated sheet, single layer sheet, multiple layer sheet, polyester fabric, nylon, canvas, HYPALON (registered trademark of Dupont in Wilmington Del.), canvas duck, rubber impregnated fabric, articulated assembly of a plurality of panels, etc. In some examples, weather shield  88  includes a pliable sheet of material. A pliable sheet or panel means that the sheet or panel can be folded over onto itself and subsequently unfolded without significant permanent deformation to the sheet or panel. The term “panel” refers to a member that has a relatively thin or small dimensional thickness compared to a dimensional width and dimensional length of the panel. For example, a panel is a member having a width and a length that are each at least five times greater than the dimensional thickness of the panel. A panel can be an assembly or a unitary piece or structure. A panel can be insulated, relatively stiff, resiliently flexible and/or a pliable sheet of material. 
       FIGS. 10-12  show another example dock leveler  12   b  constructed in accordance with the teachings disclosed herein. The example dock leveler  12   b  of the illustrated example includes an example weather shield  98 .  FIGS. 10 ,  11  and  12  correspond to  FIGS. 1 ,  4  and  6 , respectively. For example,  FIG. 10  shows deck  16  at a cross-traffic position and lip structure  18  at a retracted position.  FIG. 11  shows deck  16  at a raised position and lip structure  18  at an extended position (e.g., a fully extended position).  FIG. 12  shows deck  16  at a lowered position and lip structure  18  at another extended position (e.g., a partially extended position). 
     In this example, weather shield  98  includes a flexible sheet of material having an upper end  100  attached to header plate  66 , a lower end  102  attached to bottom panel  84 ′, and an intermediate section  104  between ends  100  and  102 . Example materials and construction of weather shield  98  are similar to that of weather shield  88  shown in  FIGS. 7-9 . Weather shield  98  has a lateral width extending across substantially a full width  96  ( FIG. 3 ) of pit  22  to create a sliding seal against wall  24  and/or against toe guard  62 . As lip structure  18  extends from the retracted position ( FIG. 10 ) to an extended position ( FIGS. 11 and 12 ), lip structure  18  carries or moves an upper end  100  of the weather shield  98  while deck-supporting foot  70  moves from a position rearward or behind the lower end  102  of the weather shield  98  to a position forward or in front of the lower end  102 . In this example, front edge  86  of bottom panel  84 ′ is proximate dock face  34  to prevent an intermediate section  104  of the weather shield  98  from drooping or sagging into open area  80 . 
       FIGS. 13-15  show an example dock leveler  12   c  that includes another example weather shield  106  disclosed herein.  FIGS. 13 ,  14  and  15  correspond to  FIGS. 1 ,  4  and  6 , respectively. For example,  FIG. 13  shows deck  16  at a cross-traffic position with lip structure  18  at a retracted position.  FIG. 14  shows deck  16  at a raised position and lip structure  18  at an extended position (e.g., a fully extended position) FIG. 15  shows deck  16  at a lowered position and lip structure  18  at another extended position (e.g., a partially extended position). 
     In this example, weather shield  106  includes a flexible sheet of material having an upper section  108  with an upper end  110  attached to header plate  66  and a lower section  112  with a lower end  114  attached to bottom panel  84 ′. Example materials and construction of upper section  108  are similar to that of weather shield  88  shown in  FIGS. 7-9 . Lower section  112  is resiliently flexible, but stiffer than upper section  108 , and is biased downward against bottom panel  84 ′ to reduce or take up slack in the more flexible upper section  108 . In some examples, lower section  112  is an insulated panel having a resiliently flexible foam core  116  (layer of thermal insulation) encased within a pliable cover  118 , where cover  118  is thinner and more thermally conductive than core  116 . In some examples, lower section  112  is a flexible sheet of material similar to weather shield  88  of  FIGS. 7-9 , but stiffened with one or more elongate stays such as, for example, fiberglass rods or strips of UHMW (ultra-high-molecular-weight polyethylene). In some examples, lower section  112  includes a resiliently flexible sheet of material that is neither pliable nor stiffened by stays, but instead achieves a non-pliable flexible resilience by virtue of its inherent material properties. Specifically, in some examples, lower section  112  comprises a sheet of UHMW. 
     Weather shield  106 , in some examples, has a lateral width extending across substantially a full width  96  ( FIG. 3 ) of pit  22  to create or provide a sliding seal against wall  24  and/or against toe guard  62 . As lip structure  18  extends from the retracted position ( FIG. 13 ) to the extended position ( FIG. 14 ), lip structure  18  carries or moves the upper end  110  of weather shield  106  while deck-supporting foot  70  moves from a position rearward or behind the lower end  112  to a position forward or in front of lower end  112 . 
       FIGS. 16-18  show another example dock leveler  12   d  disclosed herein that includes an example weather shield  120 .  FIGS. 16 ,  17  and  18  correspond to  FIGS. 1 ,  4  and  6 , respectively. For example,  FIG. 16  shows deck  16  at a cross-traffic position and lip structure  18  at a retracted position.  FIG. 17  shows deck  16  at a raised position with lip structure  18  at an extended position (e.g., a fully extended position).  FIG. 18  shows deck  16  at a lowered position and lip structure  18  at another extended position (e.g., a partially extended position). 
     In this example, weather shield  120  includes a flexible sheet of material having a front section  122  with an upper end  124  attached to header plate  66  and a rear section  126  with a lower end  128  attached to bottom panel  84  and/or to front beam  76 . Example materials and construction of front section  122  are similar to that of weather shield  88  shown in  FIGS. 7-9 . Rear section  126  is resiliently flexible but stiffer than front section  122  and is biased back toward front beam  76  to take up slack in the more flexible front section  122 . In some examples, rear section  126  is similar in material and construction to that of lower section  112  of  FIGS. 13-15 . 
     Weather shield  120 , in some examples, has a lateral width extending across substantially a full width  96  ( FIG. 3 ) of pit  22  to create or provide a sliding seal against wall  24  and/or against toe guard  62 . As lip structure  18  extends from the retracted position ( FIG. 16 ) to an extended position ( FIGS. 17 and 18 ), the lip structure  18  carries or moves the weather shield&#39;s upper end  124  while deck-supporting foot  70  moves from being behind the shield&#39;s lower end  128  to being forward or in front of lower end  128 . 
       FIGS. 19-21  show another example dock leveler  12   e  constructed in accordance with the teachings disclosed herein. The example dock leveler  12   d  is similar to dock leveler  12   d  of  FIGS. 16-18 . However, weather shield  120  of dock leveler  12   e  is flanked by two side sealing members  130  In the illustrated example, the side sealing members  130  include a right side sealing member  130   a  and a left side sealing member  130   b . Side sealing members  130  close or significantly reduce lateral air gaps  132  ( FIG. 17 ) that may exist when lip structure  18  is fully extended. In some examples, each of the side sealing members  130  is generally planar and lies substantially perpendicular to horizontal lateral direction  44 . In some examples, each of the side sealing members  130  is in sliding contact with wall  24  and/or with toe guard  62  as dock leveler  12   e  moves. 
     In some examples, side sealing members  130  are attached to and suspended from lip structure  18 . In some examples, side sealing members  130  are in sliding sealing contact with the lateral edges of weather shield  120 . In some examples, side sealing members  130  are attached to the lateral edges of weather shield  120 . In some examples, the installation of side sealing members  130  is such that the side sealing members  130  extend to a position forward or in front of the deck&#39;s front edge  54  when lip structure  18  is in the extended position, as shown in  FIG. 20 , and the deck&#39;s front edge  54  is forward of the side sealing members  130  when lip structure  18  is in the retracted position, as shown in  FIG. 19 . Each deck-supporting foot  70 , in some examples, is interposed laterally between the two side sealing members  130   a  and  130   b.    
     In some examples, each of the side sealing members  130  is a relatively thin sheet of material. In some examples, each of the side sealing members  130  has a thickness extending the full lateral distance between deck-supporting foot  70  and wall  24  and/or between deck-supporting foot  70  and toe guard  62 . In some examples, side sealing members  130  are made of a material similar to the material of weather shield  88  ( FIGS. 7-9 ). In some examples, side sealing members  130  are composed of a material and construction similar to that of lower section  112  of weather shield  106  ( FIGS. 13-15 ). In some examples, each of the side sealing members  130  is an insulated panel including a resiliently compressible foam core encased within a pliable cover. Although side sealing members  130  are shown with the example dock leveler  12   e , sealing members  130  can be provided or added to any other ones of the example dock levelers (e.g., dock levers  12   a - 12   d ) disclosed herein. 
       FIGS. 22-24  show another example dock leveler  12   f  constructed in accordance with the teachings disclosed herein. The example dock leveler  12   f  is similar to dock leveler  12   d  of  FIGS. 16-18 . However, dock leveler  12   f  has a block style side sealing member  132  that includes a central side sealing member  132   c  extending between right and left side sealing members  132   a  and  132   b . A weather shield  134  is provided that is similar to weather shield  120  of  FIGS. 16-21 . However, weather shield  134  has an upper end  136  attached to the bottom of side sealing member  132 . In some examples, side sealing member  132  includes a pliable cover  138  encasing a resiliently compressible foam core  140 , where foam core  140  fills central side sealing member  132   c  and both the right and left side sealing members  132   a  and  132   b.    
       FIGS. 25-27  show another example dock leveler  12   g  disclosed herein that includes an example weather shield  142 .  FIGS. 25 ,  26  and  27  correspond to  FIGS. 1 ,  4  and  6 , respectively.  FIG. 25  shows deck  16  at a cross-traffic position and lip structure  18  at a retracted position.  FIG. 26  shows deck  16  at a raised position and lip structure  18  at an extended position (e.g., a fully extended position).  FIG. 27  shows deck  16  at a lowered position and lip structure  18  at another extended position (e.g., a partially extended position). 
     In this example, weather shield  142  includes a flexible sheet of material having a front section  144  with an upper end  146  attached to header plate  66 , a rear section  148  with a lower end  150  attached bottom panel  84  and/or to front beam  76 , and an intermediate section  152  between sections  144  and  148 . Example materials and construction of front section  144  are similar to that of weather shield  88  shown in  FIGS. 7-9 . Rear section  148  is resiliently flexible but stiffer than front section  144  and is biased toward front beam  76  to take up slack in the weather shield  142 . In some examples, rear section  148  is similar in material and construction to that of lower section  112  of  FIGS. 13-15 . 
     Intermediate section  152 , in some examples, is stiffer than front section  144  to reduce the extent to which weather shield  142  droops or sags when lip structure  18  is retracted ( FIG. 25 ) or partially extended ( FIG. 27 ). In some examples, instead of drooping excessively when deck  16  is in the lowered position and/or when lip structure  18  is partially extended, intermediate section  152  extends generally flat or substantially horizontal underneath deck-supporting foot  70  as shown, for example, in  FIG. 27 . In some examples, intermediate section  152  is similar in material and construction to that of lower section  112  of  FIGS. 13-15 . In some examples, intermediate section  152  is generally rigid and stiffer than rear section  148 . 
     Weather shield  142 , in some examples, has a lateral width extending across substantially the full width  44  ( FIG. 3 ) of pit  22  to create a sliding seal against wall  24  and/or against toe guard  62 . As lip structure  18  extends from the retracted position ( FIG. 25 ) to an extended position ( FIGS. 26 and 27 ), lip structure  18  carries the upper end  146  of the weather shield  142  while deck-supporting foot  70  moves between a position rearward or behind the lower end  150  and a position forward or in front of lower end  150 . 
       FIGS. 28-30  show an example dock leveler  12   h  that includes another example weather shield  154  disclosed herein.  FIGS. 28 ,  29  and  30  correspond to  FIGS. 1 ,  4  and  6 , respectively.  FIG. 28  shows deck  16  at a cross-traffic position and lip structure  18  at a retracted position.  FIG. 29  shows deck  16  at a raised position and lip structure  18  at an extended position (e.g., a fully extended position) FIG. 30  shows deck  16  at a lowered position and lip structure  18  at another extended position (e.g., a partially extended position). 
     In this example, the weather shield  154  includes a flexible sheet of material having a front panel  156  with an upper end  158  attached to header plate  66 , a rear panel  160  with a lower end  162  attached to bottom panel  84  and/or to front beam  76 , a first intermediate panel  164  connected to rear panel  160 , and a second intermediate panel  166  between panels  156  and  164 . In this example, the plurality of panels  156 ,  160 ,  164  and  166  are interconnected by a plurality of joints  168  that are more flexible than panels  156 ,  160 ,  164  and  166 . Example materials of joints  168  are similar to that of weather shield  88  shown in  FIGS. 7-9 . Example materials and construction of panels  156 ,  160 ,  164  and  166  are similar in material and construction to that of lower section  112  of  FIGS. 13-15 . 
     In some examples, panels  156 ,  164  and  166  are relatively stiff and more rigid than rear panel  160 . Intermediate panels  164  and  166  are relatively stiff to reduce the extent to which weather shield  154  droops or sags when lip structure  18  is retracted ( FIG. 28 ) or partially extended ( FIG. 30 ). In some examples, instead of drooping excessively when deck  16  is in the lowered position and/or when lip structure  18  is partially extended, intermediate panel  166  extends generally flat or substantially horizontal underneath deck-supporting foot  70  as shown, for example, in  FIG. 30 . 
     Weather shield  154 , in some examples, has a lateral width extending across substantially the full width  96  ( FIG. 3 ) of pit  22  to create or provide a sliding seal against wall  24  and/or against toe guard  62 . As lip structure  18  extends from the retracted position ( FIG. 28 ) to an extended position ( FIGS. 29 and 30 ), the lip structure  18  carries or moves the upper end  158  of the weather shield  154  while deck-supporting foot  70  moves between a position rearward or behind the lower end  162  and a position forward or in front of lower end  162 . 
       FIGS. 31-33  show another example dock leveler  12   i  constructed in accordance with the teachings disclosed herein. The example dock leveler  12   i  includes an example weather shield  170  that extends over a variable length.  FIGS. 31 ,  32  and  33  correspond to  FIGS. 1 ,  4  and  6 , respectively.  FIG. 31  shows deck  16  at a cross-traffic position and lip structure  18  at a retracted position.  FIG. 32  shows deck  16  at a raised position and lip structure  18  at an extended position (e.g., a fully extended position) FIG. 33  shows deck  16  at a lowered position and lip structure  18  at another extended position (e.g., a partially extended position). 
     In this example, weather shield  170  includes a flexible sheet of material that extends or adjusts along a variable distance from a shield take-up system  172 . In some examples, the flexible sheet of material is similar to some examples of weather shield  88 , shown in  FIGS. 7-9 . A shield take-up system is any device for selectively releasing and retracting a flexible sheet of material. In the example shown in  FIGS. 31-33 , the shield take-up system  172  is a spring loaded roller. In the example shown in  FIGS. 34-36 , an example dock leveler  12   j  disclosed herein includes a shield take-up system  174  in the form of an elastic elongate member  176  attached to a flexible sheet  178 . Examples of elastic elongate member  176  include, but are not limited to, a helical spring, a pneumatic spring, an elastic cord, an elastic strap, etc. 
     Returning to the example shown in  FIGS. 31-33 , weather shield  170  covers a gap  180  between deck  16  and bottom panel  84  by spanning the distance between the point of attachment  182   a  of the weather shield  170  on lip structure  18  and shield take-up system  172  on frame  14 , front beam  76  and/or bottom panel  84 . In some examples, the locations of point  182   a  and shield take-up system  172  are reversed, where shield take-up system  172  is attached to lip structure  18 , and the point of attachment  182   a  of the weather shield  170  is on frame  14 , front beam  76  and/or on bottom panel  84 . In either example, as the distance between shield take-up system  172  and attachment point  182   a  changes (e.g., increases or decreases), shield take-up system  172  retracts or pays out weather shield  170  accordingly. 
     In the illustrated example, a shield guide member  182  is attached to deck  16  and situated between an upper section  184  of weather shield  170  and a lower section  186  of weather shield  170 . The shield guide member  182  of the illustrated example enables weather shield  170  to change travel direction upon passing across shield guide member  182 . In some examples, shield guide member  182  is a bar or rod across which weather shield  170  slides. In some examples, shield guide member  182  is a roller across which weather shield  170  travels. 
     Referring to the example shown in  FIGS. 34 and 36 , dock leveler  12   j  includes an additional shield guide member  188 . Shield guide member  188  redirects sheet  178  from traveling generally parallel relative to bottom panel  84  to traveling vertically behind front beam  76 . 
       FIGS. 37-39  illustrate another example weather shield  190  disclosed herein. In the example shown in  FIGS. 37-39 , the example weather shield  190 , in the form of a flexible sheet, extends a variable distance  192  between an upper point of attachment  194  on lip structure  18  and shield take-up member  172  attached to bottom panel  84 ′. In this example and in the examples shown in  FIGS. 31-36 , weather shields  170 ,  178  and  190  have a lateral width extending across substantially the full width  96  ( FIG. 3 ) of pit  22  to create or provide a sliding seal against wall  24  and/or against toe guard  62 . 
     To produce weather shields that fit dock pits of various widths, some example weather shields, such as those disclosed herein, can be made to different widths by assembling select shield segments from a weather shield collection of parts  196 , as shown in  FIG. 40 . In the illustrated example, the weather shield collection of parts  196  includes a main shield segment  198 , a first seal segment  200 , a second seal segment  202  and a sealing strip  204 . The weather shield collection of parts  196  can have any number of seal segments and/or other parts. In some examples, a fastener  206  provides means for interconnecting the weather shield collection of parts in various combinations. Examples of interconnecting means that may implement fastener  206  include, but are not limited to, a touch-and-hold fastener, a zipper, a series of snaps, adhesive, etc. Although some adhesives might not provide a disconnectable or detachable seam, many other example chemical fastener(s) provide a detachable seam. Some examples of a touch-and-hold faster include, but are not limited to, a hook-and-loop fastener, VELCRO, etc., where VELCRO is a registered trademark of Velcro Industries in Amsterdam, the Netherlands. 
       FIG. 40  shows the weather shield collection of parts  196  being assembled in various ways to create selectively a narrower weather shield  208 , a wider weather shield  210 , and an even wider weather shield  212 . Arrow  214  represents joining and arrow  216  represents separating main shield segment  198  and the first shield segment  200 , thereby creating selectively a wider weather shield  210  or a narrower weather shield  208 . In the illustrated example, the wider weather shield  210  includes the main shield segment  198  and the first shield segment  200 , and the narrower weather shield  208  includes the main shield segment  198  with neither the first shield segment  200  nor the second shield segment  202 . For sake of example, arrow  218  represents installing one of the assembled weather shields (e.g., a wider weather shield  210  underneath deck  16 ). 
     In some examples, fastener  206  selectively attaches sealing strip  204  or shield segment  200  or  202 . When sealing strip  204  is attached, sealing strip  204  is positioned in sliding seal contact with part (e.g., a toe guard) of an example dock leveler  12   k  and/or in sliding seal contact with wall  24  as shown, for example, in the lower right corner of  FIG. 40 . In some examples, one sealing strip  204 ′ is permanently attached to one lateral edge of main shield segment  198  while fastener  206  attaches the other sealing strip  204  to the other lateral edge of main shield segment  198  or to a shield segment  200  or  202 . In some example weather shields have two sealing strips  204 , while neither sealing strip  204  is permanently attached. Instead, fastener  206 , in some examples, is used to attach both sealing strips  204 . 
       FIG. 40  shows shield segments  200  and  202  being added or removed from only the right lateral edge of main shield segment  198 . However, in some examples, shield segments  200  and  202  are also added or removed from the left lateral edge of main shield segment  198  as well, thereby providing the assembled weather shield with a more balanced or symmetrical appearance. 
     Any suitable means can be used for attaching the example weather shields disclosed herein. Example means for attaching a weather shield to a dock leveler lip structure, frame, and/or bottom panel include, but are not limited to, screws, rivets, snaps, magnets, touch-and-hold fasteners, spring loaded clips, clamps, adhesives, and/or various combinations thereof. 
       FIGS. 41-43  show another example dock leveler  12   m  constructed in accordance with the teachings disclosed herein. The example dock leveler  12   m  includes an example weather shield  220 .  FIGS. 41 ,  42  and  43  correspond to  FIGS. 1 ,  4  and  6 , respectively.  FIG. 41  shows deck  16  at a cross-traffic position and lip structure  18  at a retracted position.  FIG. 42  shows deck  16  at a raised position and lip structure  18  at an extended position (e.g., a fully extended position).  FIG. 43  shows deck  16  at a lowered position and lip structure  18  at another extended position (e.g., a partially extended). 
     In this example, weather shield  220  includes a flexible sheet of material having a front section  222  with an upper end  224  attached to header plate  66  and a rear section  226  with a lower end  228  attached to bottom panel  84  and/or to front beam  76 . To reduce (e.g., minimize) drooping or sagging of weather shield  220 , rear section  226  is an accordion-like structure having a plurality of resilient shield panels  230  interconnected along their upper and lower edges such that each shield panel  230  is biased back toward front beam  76 . Any suitable means can be used for interconnecting or coupling panels  230 . Some example means include, but are not limited to, threads (sewn seam), screws, rivets, snaps, touch-and-hold fasteners, clamps, adhesives, ultrasonic welding, RF welding, hot plate welding, and/or various combinations thereof. In some examples, rear section  226  is a tightly folded unitary piece, where panels  230  are integrally joined along their upper and lower edges. 
     In some examples, each panel  230  includes a resiliently compressible foam core (layer of thermal insulation) encased within a pliable cover. In some examples, each panel  230  is a flexible sheet of material similar to weather shield  88  of  FIGS. 7-9 , but stiffened with one or more elongate stays, such as fiberglass rods or strips of UHMW (ultra-high-molecular-weight polyethylene). In some examples, each panel  230  includes a resilient sheet of material that is neither pliable nor stiffened by stays, but instead achieves a non-pliable flexible resilience by virtue of its inherent material properties. Specifically, in some examples, each panel  230  is a sheet of UHMW. 
     In some examples, front section  222  of weather shield  220  is of a similar construction to that of rear section  226 , where front section  222  is an accordion-like extension of rear section  226 . Some example materials and construction of front section  222  are similar to that of weather shield  88 , shown in  FIGS. 7-9 . 
     Weather shield  220 , in some examples, has a lateral width extending across substantially a full width  96  ( FIG. 3 ) of pit  22  to create or provide a sliding seal against wall  24  and/or against toe guard  62 . As lip structure  18  extends from the retracted position ( FIG. 41 ) to an extended position ( FIGS. 42 and 43 ), the lip structure  18  carries or moves the upper end  224  of the weather shield  226  while deck-supporting foot  70  moves between a position rearward or behind the lower end  228  of the weather shield  226  to a position forward or in front of lower end  228 . 
     Although certain example methods, apparatus and articles of manufacture have been described herein, the scope of the coverage of this patent is not limited thereto. On the contrary, this patent covers all methods, apparatus and articles of manufacture fairly falling within the scope of the appended claims either literally or under the doctrine of equivalents.