 |
Description  |
|
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to seals, and more particularly to
sliding seals of the type wherein sliding motion between the seal and
another member occurs. The sliding seal of this invention comprises a pile
seal member secured to a channel-shaped gripping element. A protective
arm-guard extends from one of the pile seal members or gripping elements
to prevent penetration of the pile by foreign material such as stones or
the like.
2. Description of the Prior Art
U.S. Pat. No. 3,175,256 relates to a weather-seal having a base strip and
two longitudinally extending parallel spaced rows of pile attached to the
base strip. An impervious fin of thermoplastic material is secured on edge
to the base strip in the space between the rows of pile.
U.S. Pat. No. 3,198,689 discloses a weatherseal mountable on a flange
around a door or window opening in a motor vehicle body to prevent water
and air leakage into the body. The weatherseal comprises a channel member
having gripping means by which the seal is mounted on the flange. The
gripping means comprises gripping ribs extending longitudinally along the
inside surface of the channel member, projecting toward each other from
the opposite side walls thereof. Although only one rib is shown on each
side wall, it is known in the art to provide more than one, if desired.
U.S. Pat. No. 4,114,320 discloses a door seal having a channel-shaped
gripping element, and a tubular seal secured to a portion of the outer
surface of the channel-shaped element.
It is further known in the prior art to provide a longitudinally extending
deformable seal such as a rubber gasket or the like for sealing a
swingable refrigerator door. The seal is secured to the door frame by any
suitable means, and is sealingly engaged by a surface of the door when it
is swung to its closed position.
Although the deformable seal provides an adequate seal for swingable doors,
it is unsatisfactory for roll-up type overhead doors in refrigerated
trucks, trailers or box cars. One of the problems is that the sliding
motion between the deformed or compressed seal and the door surface
results in abrasion which is potentially damaging to the seal and door.
Seal damage can result in air leakage. This, in turn, can increase the
work load on the refrigerator system and its cost of operation. In
addition, possible damage to the refrigerated perishable product can
result, particularly if the refrigeration system breaks down.
Leaf seals are also known in the art for sealing the space between the
surface of a roll-up door and the door frame. One problem with this type
of seal, in addition to the abrasion problem noted above, is that the
unevenness or irregularities in the roll-up door surface prevents securing
a good seal. Another problem is that the leaf seal is oriented to offer
more resistance to inward air flow than outward resulting in possible loss
of refrigerated air outwardly through the seal.
SUMMARY OF THE INVENTION
In accordance with this invention, preferred embodiments of a grippable
sliding seal strip are disclosed for sealing the space between a fixed
frame such as a door frame and a sliding member such as a roll-up overhead
door. The seal strip comprises an elongated channel-shaped element
mountable on the fixed frame. A base strip is secured to a portion of the
outer surface of the channel-shaped element. A longitudinally extending
row of pile has one surface thereof secured to the base strip. The
opposite free surface of the pile slidably engages the sliding member.
In another aspect of the invention, the seal strip has a flexible link
member connecting the base strip to the portion of the outer surface of
the channel-shaped element.
In more specific aspects of the invention, the flexible link member can be
a flexible rib, or a flexible tubular member.
In another aspect of the invention, the seal strip is provided with a guard
arm extending from the channel-shaped element or the base strip toward the
sliding member for preventing foreign material such as stones from
penetrating and damaging the pile of the seal member.
In more specific aspects of the invention, the guard arm is flexible, and
comprises the free end of one of the side walls of the channel-shaped
element. The guard arm can also comprise the free edge of the base strip,
or an arm integral with and extending from the tubular member.
The primary advantage of the aforementioned aspects of the invention is to
solve the aforementioned problems of prior art seals interposed between
fixed and sliding members. Such problems include, for example, inadequate
sealing and extensive abrasion damage of the seal strip and sliding
member.
The invention and its advantages will become more apparent from the
detailed description of the invention presented below.
BRIEF DESCRIPTION OF THE DRAWINGS
The details of this invention will be described in connection with the
accompanying drawings, in which:
FIG. 1 is a front elevational view of a fixed structure supporting a
sliding member shown as a roll-up overhead door;
FIG. 2 is an enlarged segmental view taken substantially along line 2--2 of
FIG. 1;
FIG. 3 is an enlarged view in section of the seal strip illustrated in FIG.
2; and
FIGS. 4, 5, 6 and 7 are views similar to FIG. 3 of other embodiments of the
seal strip of this invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1 of the drawings, a fixed structure 10 such as a garage
or the body of a refrigeration car, truck or trailer is disclosed having a
door frame 12 for supporting a sliding member such as a roll-up or
overhead door 14. The door is of the conventional type comprising a
plurality of parallel, hinged panels, not shown, which allow the door to
be vertically oriented, when closed, and substantially horizontally
oriented, when opened.
With reference to FIG. 2, and as is well known in the art, door 14 is
further provided along each side edge with a plurality of spaced housings
16, only one of which is shown, each adapted to pivotally support a shaft
18. A triangular-shaped link plate 20 is secured along one side of the
link to one end of each shaft 18, and a laterally extending stub shaft 22
secured to each link opposite the one side rotatably supports a roller 24
on roller-bearings, not shown. The rollers are rotatably captured within
elongated, chute-like roller guides 26 arranged in a substantially
inverted L-shaped orientation. Each roller guide 26 is mounted on one end
of a plate 28 of L-shaped cross-section secured to door frame 12 along
each side of the door. The opposite end or flange 30 of plate 28 supports
a seal strip 32, to be described more fully with reference to FIG. 3.
Referring to FIG. 3, seal strip 32 comprises an elongated channel-shaped
gripping element 34 essentially of the type disclosed and described in
U.S. Pat. No. 3,198,689. The channel-shaped element 34 has a wire carrier
36 preferably covered by a flexible polymeric material. The wire carrier
strengthens the element and improves its gripping power. The element has
gripping ribs 38 formed from any suitable material running along and
protruding from the inside surface of each wall of element 34. Gripping
ribs 38 help to ensure that seal strip 32 is not inadvertently pulled off
the end of flange 30 once it is mounted thereon.
An elongated pile seal member 40 essentially of the type disclosed and
described in U.S. Pat. No. 3,175,256 has a base strip 42 of any suitable
material secured to a portion of the outer surface of channel-shaped
element 34. The portion of the outer surface to which base strip 42 is
secured depends upon the orientation of flange 30 relative to outer door
surface 44 (FIG. 2). Pile seal member 40 comprises spaced rows of pile 46
secured at one end surface to the base strip, and the opposite free end
adapted to slidably engage outer door surface 44. A moisture impervious
barrier fin 48 of any suitable material is mounted in the space between
the rows of pile 46 with one end thereof preferably secured to base strip
42.
One edge of base strip 42 has an arm 50 transverse to and extending
outwardly from the base strip toward and preferably into engagement with
outer door surface 44. Arm 50 forms a guard in front of pile 46 extending
between flange 30 and outer door surface 44 to prevent foreign objects
such as dirt, oil, water or stones from penetrating the pile and damaging
it. This is particularly possible in those applications where the seal
strip is incorporated on sliding doors of fast moving refrigeration
vehicles such as trucks. Arm 50 is preferably flexible and of a length so
that in its guard position as seen in FIG. 2, the rounded free end 52
thereof bears against outer door surface 44 with a predetermined pressure.
With reference to the embodiments of seal strip 32 illustrated in FIGS.
4-7, parts similar to parts shown and described in FIG. 3 will be
designated by the same numerals.
Referring to the FIG. 4 embodiment of the invention, guard arm 50 is
integral with and extends outwardly from one of the side walls of
channel-shaped element 34. In broken lines, pile seal member 40 is shown
in an alternate position for those sealing applications in which plate
flange 30 is oriented substantially perpendicular to the outside door
surface 44.
In the embodiment of seal strip 32 illustrated in FIG. 5, a support strip
54 of any suitable material is secured to an outer surface of
channel-shaped element 34. A flexible substantially Y-shaped link member
56 preferably formed from any suitable polymeric material has one leg 58
connected to support strip, another leg 60 connected to base strip for
supporting pile, and the last leg extending in front of pile 46 to form
guard arm 50. Support strip 54 and link member 56 may be extruded as one
piece. Link member 56 is further oriented at an angle to outside door
surface 44 so that in operation pile seal member 40, leg 60 and arm 50 are
flexed for applying sealing pressure against door 14. Link member 56
further serves to deflect in operation to compensate for wide tolerances
developed over the functional life of the seal and door.
With reference to FIG. 6, flexible link member 56' is tubular, and of a
substantially right-triangular cross-section. In FIG. 7, link member 56"
is also tubular, but of a substantially rectangular cross-section. In FIG.
7, guard arm 50 is integral with and extends outwardly from the link
member.
Existing door frames on trailers, trucks or the like are provided with
vertically extending flanges for, among other things, supporting known
leaf type seals. Such door frames may be readily retrofitted with the new
grippable sliding seal strip of this invention which requires no fastening
means to the existing door frame. The new sliding seal can further be
readily replaced when worn out. To provide a continuous seal at the top of
the door, a horizontal framing member may be added to the door frame by
screws or the like for supporting a flange interposed between the existing
vertical flanges. A bulb type seal may be added to the bottom of the door
to provide a fully sealed roll-up door sealed on the top, bottom and each
side thereof.
While presently preferred embodiments of the invention have been shown and
described with particularity, it will be appreciated that various changes
and modifications may suggest themselves to one having ordinary skill in
the art upon being apprised of the present invention. It is intended to
encompass all such changes and modifications as fall within the scope and
spirit of the appended claims.
* * * * *
|
|
 |
|
 |
Description |
|
