DRAFT SHIELD FOR A LOADING DOCK SHELTER

ECRAN ANTI-COURANT D'AIR POUR AUVENT DE QUAI DE CHARGEMENT

English Abstract

At a truck loading dock, a flexible draft shield (32) helps seal a lower inner
corner of a dock shelter. Instead of a foam core, the draft shield includes a
resiliently flexible frame (50) that supports a pliable cover (48). In some
embodiments, the frame includes a spring steel loop that is able to flex upon
being squeezed between two members of the dock shelter. In some cases, the
draft shield is hollow and open at the bottom.

French Abstract

La présente invention concerne un écran souple anti-courant d'air (32) équipant un quai de chargement de camions pour créer une fermeture plus étanche au niveau du coin intérieur bas d'un auvent de quai. Dans cet écran anti-courant d'air, le coeur de mousse a été remplacé par une armature souple par élasticité (50) servant de support à un élément couvrant souple (48). Selon certains modes de réalisation, l'armature comporte un ressort à lame en boucle capable de fléchir sous l'effet d'une compression s'exerçant entre deux éléments de l'auvent de quai. Dans certains cas, l'écran anti-courant d'air est creux et ouvert vers le bas.

Claims

Claims
1. A draft shield for a dock shelter, wherein the dock shelter is movable
between a standby position disengaged from a vehicle and a vehicle-engaging
position, the draft shield comprising:
a frame consisting of a solid material and being resiliently movable between
an
extended position and a collapsed position, wherein the frame is movable to
the
extended position when the dock shelter is in the standby position and the
frame is
movable to the collapsed position when the dock shelter is in the vehicle-
engaging
position; and
a pliable cover overlaying the frame and adapted to remain engaged with the
dock shelter as the dock shelter moves between the standby position and the
vehicle-
engaging position.
2. The draft shield of claim 1, wherein the draft shield is hollow.
3. The draft shield of claim 1, wherein the draft shield has an open
bottom.
4. The draft shield of claim 1, wherein the frame includes a resilient strap.
5. The draft shield of claim 1, wherein the solid material is steel.
6. The draft shield of claim 1, wherein the frame includes a resilient loop
that helps support the pliable cover.
7. The draft shield of claim 1, wherein the pliable cover includes a first
hem through which the frame extends.
8. The draft shield of claim 7, wherein the pliable cover includes a second
hem through which the frame extends.
9. The draft shield of claim 1, wherein the draft shield has a horizontal
span and a vertical height, with the horizontal span being greater than the
vertical
height.
10. A dock shelter for use at a loading dock that facilitates the loading or
unloading of a vehicle at a building, the dock shelter comprising:
a projecting member attachable to the building;
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a laterally extending member movably connected to the projecting member
and being adapted to be engaged by the vehicle, wherein the laterally
extending
member is movable from a standby position to a vehicle-engaging position in
response to the vehicle backing into the laterally extending member; and
a hollow draft shield disposed at a lower end of the projecting member and
extending to the laterally extending member to obstruct airflow therebetween.
11. The dock shelter of claim 10, wherein the hollow draft shield has an
open bottom.
12. The dock shelter of claim 10, wherein the hollow draft shield includes
a pliable cover overlaying a resilient frame.
13. The dock shelter of claim 12, wherein the resilient frame includes a
resilient strap.
14. The dock shelter of claim 12, wherein the resilient frame is comprised
of steel.
15. The dock shelter of claim 12, wherein the resilient frame includes a
resilient loop that helps support the pliable cover.
16. The dock shelter of claim 12, wherein the pliable cover includes a first
hem through which the resilient frame extends.
17. The dock shelter of claim 16, wherein the pliable cover includes a
second hem through which the resilient frame extends.
18. The dock shelter of claim 10, wherein the hollow draft shield has a
horizontal span and a vertical height, with the horizontal span being greater
than the
vertical height.
19. A dock shelter for use at a loading dock that facilitates the loading or
unloading of a vehicle at a building, the dock shelter comprising:
a projecting member attachable to the building;
a laterally extending member movably connected to the projecting member
and being adapted to be engaged by the vehicle, wherein the laterally
extending
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member is movable from a standby position to a vehicle-engaging position in
response to the vehicle backing into the laterally extending member;
a frame disposed at a lower end of the projecting member and extending to the
laterally extending member, wherein the frame consists of a solid material and
is
resiliently movable between an extended position when the laterally extending
member is in the standby position and a collapsed position when the laterally
extending member is in the vehicle-engaging position; and
a pliable cover overlaying the frame to provide an obstruction to vertical
airflow between the projecting member and the laterally extending member.
20. The dock shelter of claim 19, wherein the frame and the pliable cover
comprise a draft shield that is hollow.
21. The dock shelter of claim 20, wherein the draft shield has an open
bottom.
22. The dock shelter of claim 19, wherein the frame includes a resilient
strap.
23. The dock shelter of claim 19, wherein the solid material is steel.
24. The dock shelter of claim 19, wherein the frame includes a resilient
loop that helps support the pliable cover.
25. The dock shelter of claim 19, wherein the pliable cover includes a first
hem through which the frame extends.
26. The dock shelter of claim 25, wherein the pliable cover includes a
second hem through which the frame extends.
27. The dock shelter of claim 20, wherein the draft shield has a horizontal
span and a vertical height, with the horizontal span being greater than the
vertical
height.
28. A dock shelter for use at a loading dock that facilitates the loading or
unloading of a vehicle at a building, the dock shelter comprising:
a projecting member attachable to the building;
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a laterally extending member movably connected to the projecting member
and being adapted to be engaged by the vehicle, wherein the laterally
extending
member is movable from a standby position to a vehicle-engaging position in
response to the vehicle backing into the laterally extending member;
a frame disposed at a lower end of the projecting member, wherein the frame
is resiliently movable between an extended position when the laterally
extending
member is in the standby position and a collapsed position when the laterally
extending member is in the vehicle-engaging position; and
a pliable cover overlaying the frame, whereby the frame and the pliable cover
comprises a draft shield having a span and a height, wherein the span extends
between
the projecting member and the laterally extending member, and the height is
perpendicular to and less than the span.
29. The dock shelter of claim 28, wherein the frame and the pliable cover
comprise a draft shield that is hollow.
30. The dock shelter of claim 29, wherein the draft shield has an open
bottom.
31. The dock shelter of claim 28, wherein the frame includes a resilient
strap.
32. The dock shelter of claim 28, wherein the frame is comprised of steel.
33. The dock shelter of claim 28, wherein the frame includes a resilient
loop that helps support the pliable cover.
34. The dock shelter of claim 28, wherein the pliable cover includes a first
hem through which the frame extends.
35. The dock shelter of claim 34, wherein the pliable cover includes a
second hem through which the frame extends.
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Description

CA 02460851 2004-03-15
WO 2004/013432 PCT/US2002/024365
DRAFT SHIELD FOR A LOADING DOCK SHELTER
Back ound of the Invention
Field of the Invention
The subj ect invention generally pertains to loading dock shelters, and more
specifically to a device that helps seal a lower comer of the dock shelter.
Description of Related Art
When an exterior doorway of a building is used for loading and unloading
trucks, the doorway often includes a dock shelter to help shield against
weather. The
dock shelter seals off gaps that might otherwise exist between the exterior
face of the
building and the back end of the truck. Dock shelters often have proj ecting
members
that,protrude outwardly.from the face of the building and run generally along
the top
and lateral sides of the doorway. From a protruding edge of the proj ecting
members, a
top extending member and two laterally extending members may extend inward and
generally parallel to the building face to help seal against the truck's top
and sides,
respectively. The laterally extending members can be made of fabric, hinged
panels,
or flexible foam. Portions of the truck's rear bottom edge are often partially
sealed off
by dock bumpers and the lip extension of a dock leveler. The remaining gaps
are two
inner bottom corners of the dock shelter at the lower back sides of the truck.
These
gaps are often partially sealed by draft pads attached to the lower ends of
the
projecting members.
Examples of draft pads can be found in U. S. Patents 4,885,881; 3,792,559 and
6,014,844. In these examples, the draft pads comprise a compressible foam core
covered with pliable fabric. The foam core enables the pad to be compressed by
a
truck backing into the dock shelter and provides the pad with compliance for
filling
certain air gaps within the shelter. The fabric cover helps protect the foam
core from
dirt, wear and weather.
To help prevent the draft pad from sagging, the foam core includes a certain
amount of bulk for structural support. Except for the added expense, such bulk
may
not be a problem with today's conventional dock shelters. However, newer dock
shelters may be best served by a draft seal having a sleeker, more lightweight
design.

CA 02460851 2004-03-15
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Summary of the Tnvention
In some embodiments, a draft shield for a dock shelter includes a resilient
frame with a pliable fabric cover.
In some embodiments, the frame of a draft shield is made of spring steel.
In some embodiments, the frame of a draft shield forms a loop.
In some embodiments, a draft shield is hollow.
In some embodiments, a draft shield includes an open bottom.
In some embodiments, the cover of a draft shield includes a pocket or hem that
holds the frame of the seal.
In some embodiments, a draft shield has an overall height that is less than
its
horizontal span.
Brief Description of the Drawings
Figure 1 is a perspective view of a truck backing into a dock shelter that
includes a draft shield, wherein the dock shelter is in a standby position.
Figure 2 is a cross-sectional view taken along line 2-2 of Figure 1.
Figure 3 is similar to Figure 2, but with the vehicle having forced the dock
shelter into a vehicle-engaging position.
Figure 4 is a perspective view of one part of a dock shelter and its draft
shield.
Figure 5 is an exploded view of the draft shield of Figures 1- 4 and with part
of the cover cut away.
Figure 6 is a perspective view of the draft shield of Figures 1- 5, but with
the
cover omitted to show other details.
Figure 7 is similar to Figure 2, but with the cover omitted to show the draft
shield in an extended position.
Figure 8 is similar to Figure 3, but with the cover omitted to show the draft
shield in a collapsed position.
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Description of the Preferred Embodiment
Figure 1 shows a dock shelter 10 attached to an exterior face of a building
12.
Building 12 includes a doorway 14 through which a vehicle 16, such as a truck
or
trailer, may load and unload its cargo. Building 12 may also optionally
include a dock
leveler 18 and bumpers 20. Dock shelter 10 is situated generally along lateral
edges
of doorway 14 to help seal gaps that may otherwise exist between the exterior
face of
building 12 and a back end 22 of vehicle 16.
Dock shelter 10 has a right projecting member 24 and a left projecting member
26 that extend outward from building 12. Both projecting members 24 and 26
have
respective laterally extending members 28 and 30 that extend generally inward
toward
vehicle 16. As vehicle 16 backs into dock shelter 10, laterally extending
members 28
and 30 can pivot from a standby position of Figures 1 and 2 to a vehicle-
engaging
position of Figure 3. The term, "pivot" broadly refers to one member rotating
or
moving relative to another, wherein the rotation is made possible by any means
including, but not limited to, a hinge or by way of deflection.
When vehicle 16 moves members 28 and 30 to the vehicle-engaging position,
a draft shield 32 is deflected or compressed in a lower inside comer between
projecting member 24 and laterally extending member 28 to help obstruct
airflow in
that area. Likewise, another draft shield 34, which is a left-hand version of
draft
shield 32, is installed at the lower inside corner of projecting member 26 and
laterally
extending member 30.
Projecting members 24 and 26 and laterally extending members 28 and 30
represent a myriad of structural possibilities. Some examples of projecting
members
24 include, but are not limited to, the projecting members being made of foam
(compressible and resilient), wood, fabric, steel, and various combinations
thereof.
The same is true for laterally extending members 28 and 30. More specific
examples
of projecting members and their laterally extending members include, but are
not
limited to, an L-PAD made of a compressible, resilient foam where the
projecting
members can each be integrally joined as a unitary piece to their respective
laterally
extending members; a model WG-402 dock shelter having wood-framed projecting
members with laterally extending members made of fabric; and ELIMINATOR
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CA 02460851 2004-03-15
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having foam projecting members with laterally extending members made of
fabric;
and a dock shelter whose proj ecting members are normally rigid but are able
to
collapse without extensive permanent damage upon impact of a truck. The L-PAD,
WG-402, and ELIMINATOR are products of Frommelt Products Corporation, of
Milwaukee, Wisconsin. Typical dock shelters also include a header 36 that may
be
similar in structure and function as the projecting and laterally extending
members
just described; however, header 36 is for sealing along an upper rear edge of
vehicle
16. Based on the foregoing, one of skill in the art will appreciate that the
term "dock
shelter" as used herein may encompass traditional dock shelters, certain dock
seals,
and "hybrid" products such as the ELIMINATOR.
Referring to Figure 4, in some embodiments, projecting member 24 comprises
a semi-rigid plastic panel 38 attached to a frame 40 made of standard two-by-
fours
(lumber having a nominal cross-section oft-inches by 4-inches). .Frame 40 can
be
supported by a beam 42 that includes a flange 44 for attaching beam 42 to the
face of
building 12. Laterally extending member 28 can also be made of semi-rigid
plastic
with one vertical edge fastened to frame 40. In some embodiments, panel 38 and
member 28 are made of 1/8-inch thick high molecular weight polyethylene.
Although
other materials and thickness can be used, laterally extending member 28
preferably
has sufficient flexibility to resiliently pivot or deflect relative to proj
ecting member
24, or a hinge connecting members 24 and 28 may be used. In some cases, adding
spring steel strips 46 can increase the stiffness and/or resilience of
laterally extending
member 28.
The construction of draft shield 32 can be as shown in Figures 5 and 6. Figure
5 shows an exploded view of draft shield 32 with some portions cut-away to
show
detail underneath. Figure 6 shows draft shield 32 with a pliable cover 48
removed to
show more clearly a resilient frame 50 that supports cover 48. A two-by-four
backer
52 allows draft shield 32 to be mounted to projecting member 24 by way of
brackets
54 or by some other appropriate mounting hardware. Frame 50 includes a
resilient
strap 56 made of a flexible solid material, such as spring steel. The term,
"solid
material" refers to a material that is non-cellular and to a member whose base
substance is impervious to liquid water. For example, a perforated strap made
of
spring steel may allow liquid water to pass through any perforations, yet the
base
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substance itself, steel, is impervious to liquid water. Strap 56 can be formed
in a loop
58 by inserting strap 56 through a first hem 60 in cover 48, attaching one end
62 of
strap 56 to backer 52 via fasteners 64, and attaching an opposite end 66 of
strap 56 to
backer 52 via fasteners 68. Another strap 70 inserted into a second hem 72 and
attached to backer 52 via fasteners 74 can be used to help support a rear
portion of
cover 48. Cover 48 overlays strap 56, strap 70 and backer 52 to obstruct
airflow or
drafts at the lower inside corner of projecting member 24 and laterally
extending
member 28. Cover 48 can be made of pliable vinyl or some other pliable
material or
fabric.
The function of draft seal 32 can be further understood with reference to
Figures 2, 3, 7 and 8. Figures 7 and 8 are the same as Figures 2 and 3
respectively,
but with cover 48 omitted to show how frame 50 flexes. As vehicle 16 backs
into
dock shelter 10, vehicle 16 forces laterally extending member 28 to-move from
its
standby position of Figures 2 and 7 to its vehicle-engaging position of
Figures 3 and 8:.
As this occurs, vehicle 16 also forces laterally extending member 28 to
resilient bend.
frame 50 from an extended position of Figure 7 to a collapsed position of
Figure 8.
The pliability of cover 48 allows cover 48 to follow the movement of frame 50
to
shield against upward or downward drafts at the lower inside corner of
projecting
member 24 and laterally extending member 28: Shielding against such drafts can
be
most effective when cover 48 can further seal or brush against the top of
bumper 20.
Draft shield 32 is preferably hollow and open at the bottom to allow shield 32
to exhaust and take-in air upon moving to the collapsed and extended positions
respectively.
Refernng to Figure 4, to minimize weight and size, draft shield 32 has a
height
76 that is appreciably less than its horizontal span 78, wherein the span is
measured in
a direction perpendicular to projecting member 24 and parallel to the face of
building
12.
Although the invention is described with respect to a preferred embodiment,
modifications thereto will be apparent to those skilled in the art. Therefore,
the scope
of the invention is to be determined by reference to the claims, which follow.
5

Representative Drawing