WEATHER SHIELD FOR UNDERNEATH A DOCK LEVELER WITH A TRANSLATING LIP
A dock leveler with a vertically adjustable deck and horizontally translating lip includes a weather shield that helps shelter a pit area underneath the lip and the deck. The dock leveler and shield system is particularly suited for serving trucks that include a rear liftgate. An upper edge of the weather shield seals against and moves with the lip of the dock leveler, and a lower edge of the shield can be attached to a lower dividing panel. The lower dividing panel (sometimes known as an ISO panel) isolates the deck of the dock leveler from a liftgate-receiving receptacle within the pit area. The weather shield accommodates the lip's horizontal movement and the deck's vertical movement. The shield is such that it further accommodates a vertically moving door panel that can close in front of both the deck and the lip.
The subject disclosure generally pertains to loading docks and more specifically to a shield system for sheltering an area underneath a dock leveler.
BACKGROUND OF RELATED ARTA 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. An extension plate or lip extends outward from the deck's front edge to span the gap between the rear of the truck bed and the front edge of the deck.
The deck and lip are usually moveable between a stored position and an operative position. When in the stored position, the deck may be either vertical or horizontal, depending on the style of dock leveler. In addition, dock levelers may be equipped with a variety of different lips, including fixed (immovable) lips, pivotally-mounted, or rotating, lips, and linearly-moving, or telescopic, lips. Regardless of what style of lip is utilized, the lip, in the operative position, is intended to extend from the deck's front edge and rest upon the truck bed to form a bridge between the two, thereby allowing personnel and material handling equipment to 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, some type of seal is usually installed around the perimeter of the doorway. Such seals are typically installed along the upper and side edges of the doorway to help seal any air gaps that may otherwise exist between the face of the building and the rear of the vehicle. The dock leveler lip resting upon the rear of the vehicle is often relied upon to seal most of the doorway's lower edge.
The area or pit underneath a dock leveler'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 loose a significant amount of heat by thermal conduction through the deck, as cold outside air cools the ramp from underneath. Thus, regardless of whether the outside air is colder or warmer than the inside air, it may be beneficial to shield the underside of a dock leveler from outside air.
Although attempts have previously been made to shield, or seal, the underside of fixed-lip and pivotally-mounted-lip dock leveler from outside air, a need still exists for an under-leveler shield that provides an effective and consistent shield for underneath of a dock leveler with a telescopic lip. Because telescopic lips move linearly relative to the deck, they effectively change the length of the dock leveler and provide a unique set of challenges to those attempting to shield the area below the leveler.
First, the shield must provide an effective environmental barrier regardless of lip position (e.g., retracted or extended). A translating lip can limit the choices for attaching an effective shield.
Second, because a translating lip moves linearly, the upward travel requirement for the dock leveler's deck is considerably less than that for pivotally mounted lips because decks with translating lips do not need to be raised as high for the lip to clear the rear edge of the truck/trailer and subsequently lowered upon the vehicle bed. This means that a different, unique shield may be needed.
Third, the shield must accommodate the movement of a telescopic lip and provide an effective environmental barrier without interfering with the operation of the lip or leveler.
Fourth, some (but not all) translating lips include a series of slits that are open to outdoor air when the lip extends beyond the front edge of the deck. A conventional lip seal terminating near the deck's front edge can fail to close off such slits.
Fifth, dock levelers with translating lips are often associated with a vertically moving door panel that closes in front of the dock leveler by descending upon a lower dividing panel (sometimes known as an ISO panel). The existence of such a door, lower dividing panel, and a liftgate-receiving receptacle thereunder, further complicates the problem of sealing the area underneath dock levelers with a translating lip. Moreover, dock leveler shield system should be easy to install and easily customized to accommodate various parts of the dock leveler assembly.
Consequently, a need still exists for an under-leveler seal system that overcomes the limitations of current seal systems.
The use of a flexible curtain, rather than a thicker, more rigid structure, enables shield system 12 to be readily adapted to fit a wide variety of dock levelers and pits. For example, a curtain can be custom cut to size at the installation site, and various cutouts can be made so that the curtain does not interfere with the operation of the dock leveler. Such trimming is not readily accomplished with thicker foam seals, especially if they are encased within a fabric covering. Moreover, a thick foam seal takes up more space underneath a dock leveler than does a relatively thin curtain. Although a curtain-style shield is readily applied to a wide variety of dock levelers, shield 14 is particularly suited for dock levers that have a telescoping or translating lip. Because a flexible curtain is so versatile, shield system 12 can be applied to a wide variety of dock levelers.
Dock leveler 18, for example, comprises a vertically adjustable deck 20 and a telescopic lip 22 that can translate linearly relative to deck 20. The vertical movement of deck 20 can be by virtue of deck 20 pivoting about its rear edge to raise or lower a front edge 24 of the deck, or deck 20 could be supported by a mechanism that moves deck 20 up and down in a linear manner. Both modes of operation are well known to those of ordinary skill in the art. Examples of dock leveler 18 (without shield system 12) are explained in more detail in U.S. Pat. Nos. 4,455,703 and 4,662,021, which are specifically incorporated by reference herein.
The operating sequence of dock leveler 18 and shield system 12 may begin with deck 20 in its stored, cross-traffic position, as shown in
To help shield pit area 16, a front panel 36 of shield 14 has an upper edge 38 attached to lip 22 and a lower edge 40 anchored at some convenient location. To inhibit air from blowing through a series of slits 42 that might exist in lip 22, upper edge 38 of shield 14 is preferably attached to lip 22 somewhere between a distal edge 44 of lip 22 and where the series of slits 42 begin. For lips without slits, the point where upper edge 38 attaches to lip 22 is less critical. Upper edge 38 of shield 12 is spaced at least some distance from distal edge 44 to allow lip 22 to rest solidly upon bed 34.
As for lower edge 40 of shield 14, in some cases, lower edge 40 is attached to a lower panel 48 (sometimes known as an ISO panel) that provides an insulated divider in pit 16, just above a liftgate-receiving receptacle 50. Receptacle 50 provides clearance for vehicles that have a rear liftgate 52. The insulating properties of panel 48 help isolate dock leveler 18 from receptacle 50.
To help seal off side areas underneath lip 22, shield 14 may comprise two side panels 54 extending from front panel 36. Side panels 54 extend on each side of lip 22 to provide additional sealing when lip 22 projects beyond a front face 56 of dock 10. When lip 22 extends beyond front face 56 of dock 10, lip 22 extends beyond the pit walls that inherently provide an environmental barrier. As such, a need exists for an environmental barrier below lip 22 when the lip extends beyond the pit walls. Side panels 54 help meet that need by moving with lip 22, even when lip 22 extends beyond front face 56, thereby bridging the air gap that would otherwise exist in front of dock face 56 (see
Shield 14, including front panel 36 and side panels 54, can be made of any pliable or semi-flexible material including, but not limited to, nylon, canvas, HYPALON (Dupont trademark), canvas duck, rubber impregnated fabric, foam, etc. Shield system 12 may also include one or more generally horizontal rods 60 attached to front panel 36 to help ensure that shield 36 hangs uniformly and extends nearly or completely across the entire width of pit 16 for adequate sealing. Rods 60 may be made of steel, plastic, or a different material that is heavier and more rigid than shield 14 and may be sewn or otherwise attached to shield 14.
Attaching upper edge 38 of shield 14 to telescopic lip 22 helps ensure an adequate seal regardless of lip position, but it also presents unique challenges that are not encountered with fixed or rotating lip levelers because shield 14 moves as the lip 22 extends and retracts. Thus, when lip 22 is in the extended position shown in
When dock leveler 18 is in the position of
The pivotal mounting of shield 96 can be by way of a hinge 102 or by virtue of the shield's resilient flexibility. The design of shield 96 can be such that the flexing or pivoting action can be set to occur at a lower edge 104 of shield 96, although such flexure or pivoting occurring at other locations along the height of shield 96 is possible. The flexing or pivoting motion not only allows lip 22 to extend and retract but also accommodates vertical movement of deck 20.
As an alternative to the spring loaded telescopic frame 107 of
At least some of the aforementioned embodiments include one or more features and/or benefits including, but not limited to, the following:
In some embodiments, a dock leveler with a translating lip includes a weather shield with an upper edge that moves with the translation of the lip.
In some embodiments, a dock leveler with a translating lip includes a shield that extends from the lip to a lower dividing panel that is underneath the dock leveler's deck. The dividing panel helps isolate the deck from a liftgate-receiving receptacle that's in a pit area below the dock leveler.
In some embodiments, a dock leveler with a translating lip includes a shield comprising a front panel interposed between two side panels, whereby effective sealing can still occur even if the lip extends beyond a front face of the loading dock.
In some embodiments, a weather shield helps obstruct airflow through a series of slits in a translating lip of a dock leveler.
In some embodiments, a weather shield helps protect a dock leveler that is associated with a lower dividing panel (e.g., an ISO panel) and a vertically moving door that closes down against the panel (or against the shield overlaying the dividing panel).
In some embodiments, a conventional dock leveler with a translating lip is retrofitted with an appropriate weather shield.
In some embodiments, a dock leveler with a translating lip includes a weather shield that is designed such that the shield can be flexible or rigid, and the shield can be made of various materials including, but not limited to, sheet metal, plastic or fabric.
In some embodiments, a weather shield works in conjunction with a flexible seal to help block off air that might otherwise flow between a dock bumper and a translating lip of a dock leveler.
Although the invention is described with respect to a preferred embodiment, modifications thereto will be apparent to those of ordinary skill in the art. The scope of the invention, therefore, is to be determined by reference to the following claims:
Claims
1. A weather barrier for a dock leveler disposed within a dock pit, wherein the dock leveler includes a lip extending from a front end of a deck, the front end of the deck is movable between a raised position and a lowered position relative to the dock pit, and the lip is translatable in a forward direction from a retracted position to an extended position relative to the front end of the deck, the weather barrier comprising:
- a shield comprising a lower edge and an upper edge, the shield is disposed below the deck and is rotationally mounted to the dock pit and biased in a rearward direction opposite the forward direction, such that the upper edge of the shield engages an underside of the lip with the lip in the extended position, and such that the shield can rotate towards the forward direction while maintaining contact with the lip as the dock leveler descends.
2. The weather barrier of claim 1, wherein the upper edge of the shield is curved.
3. The weather barrier of claim 1, wherein the shield comprises a pliable sheet supported by a relatively rigid frame.
4. The weather barrier of claim 3, wherein the relatively rigid frame is telescopic.
5. The weather barrier of claim 1, wherein the shield includes a bend about an intermediate axis between the upper edge and the lower edge.
6. The weather barrier of claim 1, and including a biasing element operatively connected to the shield to bias it in the rearward direction.
7. A dock leveler disposed within a dock pit and being adapted to engage a vehicle, the dock leveler comprising:
- a deck with a front end that is vertically adjustable between a raised position and a lowered position;
- a lip extending from the front end of a deck and being translatable in a forward direction from a retracted position to an extended position relative to the front end of the deck; and
- a shield comprising a lower edge and an upper edge, the shield is disposed below the deck and is rotationally mounted to the dock pit and biased in a rearward direction opposite the forward direction, such that the upper edge of the shield engages an underside of the lip with the lip in the extended position, and such that the shield can rotate towards the forward direction while maintaining contact with the lip as the dock leveler descends.
8. The dock leveler of claim 7, wherein the upper edge of the shield is curved.
9. The dock leveler of claim 7, wherein the shield comprises a pliable sheet supported by a relatively rigid frame.
10. The dock leveler of claim 9, wherein the relatively rigid frame is telescopic.
11. The dock leveler of claim 7, wherein the shield includes a bend about an intermediate axis between the upper edge and the lower edge.
12. The dock leveler of claim 7, and including a biasing element operatively connected to the shield to bias it in the rearward direction.
13. A weather barrier for a dock leveler disposed within a dock pit, wherein the dock leveler includes a lip extending from a front end of a deck, the front end of the deck is movable between a raised position and a lowered position relative to the dock pit, and the lip is translatable in a forward direction from a retracted position to an extended position relative to the front end of the deck, the weather barrier comprising:
- a lower shield coupled to the dock pit; and
- an upper shield coupled to the lip and translatable therewith, the upper shield engages the lower shield in response to the lip translating from the retracted position to the extended position, the upper shield disengages the lower shield in response to the lip translating from the extended position to the retracted position.
14. The weather barrier of claim 13, wherein the lower shield remains engaged with the upper shield when the lip is in the extended position even as the front end of the deck moves between the raised position and the lowered position.
15. The weather barrier of claim 13, wherein at least one of the lower shield and the upper shield is resiliently flexible.
16. A dock leveler having a lip extending from a front end of a deck, the front end of the deck is movable between a raised position and a lowered position relative to a dock pit, and the lip is translatable in a forward direction from a retracted position to an extended position relative to the front end of the deck, the dock leveler comprising:
- a lower shield coupled to the dock pit; and
- an upper shield coupled to the lip and translatable therewith, the upper shield engages the lower shield in response to the lip translating from the retracted position to the extended position, the upper shield disengages the lower shield in response to the lip translating from the extended position to the retracted position.
17. The dock leveler of claim 16, wherein the lower shield remains engaged with the upper shield when the lip is in the extended position even as the front end of the deck moves between the raised position and the lowered position.
18. The dock leveler of claim 16, wherein at least one of the lower shield and the upper shield is resiliently flexible.
19. A dock leveler adapted to engage a vehicle, the dock leveler comprising:
- a deck that is vertically adjustable;
- a lip supported by the deck, the lip includes a proximal edge disposed underneath the deck and a distal edge extending outward beyond the deck, the lip translates relative to the deck; and
- a shield extending downward from the lip, the shield comprises a front panel and two side panels, wherein the front panel is interposed between the two side panels and lies generally perpendicular thereto.
20. The dock leveler of claim 19, wherein the shield comprises a flexible curtain.
21. The dock leveler of claim 19, wherein the proximal edge moves relative to the deck and the distal edge moves relative to the lip as the lip translates.
22. The dock leveler of claim 19, wherein the lower edge is mounted at a substantially fixed location.
23. A weather barrier for a dock leveler adapted to engage a vehicle, the weather barrier comprising:
- a shield extending downward from a lip supported by an adjustable deck, the shield having a front panel and two side panels, wherein the front panel is interposed between the two side panels and lies generally perpendicular thereto, and wherein the lip includes a proximal edge disposed underneath the deck and a distal edge extending outward beyond the deck such that the lip translates relative to the deck.
24. The weather barrier of claim 23, wherein the shield comprises a flexible curtain.
25. The weather barrier of claim 23, wherein the proximal edge moves relative to the deck and the distal edge moves relative to the lip as the lip translates.
26. The weather barrier of claim 23, wherein a lower edge of the shield is mounted at a substantially fixed location.
Type: Application
Filed: Nov 19, 2007
Publication Date: May 21, 2009
Inventors: Andreas Bettendorf (Kunzell), Charles J. Digmann (Dubuque, IA), David J. Hoffmann (Peosta, IA), Matthew C. McNeill (Mequon, WI), Paul D. Rowlett (Mequon, WI)
Application Number: 11/942,249
International Classification: E01D 18/00 (20060101);