Access shield for uncovered refrigerated units

Energy losses from market refrigerated display cases, which are normally open, can be dramatically reduced by use of an access shield according to the present invention. The access shield comprises a plurality of transparent and resilient panels, each panel being adjacent to at least one other and having an overlapping relationship with the adjacent panel. The panels may be mounted in a rigid frame and allow access therethrough by stretching and bending of one or more of the panels along the overlapped line. The plurality of panels may also be fitted to a spring tensioned roller and stretched across the aperture of the display refrigeration case. In another embodiment, the plurality of panels may each be attached at an opposite ends to a holder having a bow tie shaped protrusion which is urged into a receiving indentation a fixture to temporarily lock the panel in a predetermined position and yet to permit free rotation within a sector to facilitate access.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to the field of refrigerated apparatus and in 
particular to means for temporarily opening and closing access apertures 
to refrigerated devices. 
2. Description of the Prior Art 
Refrigerated display apparatus in markets have typically used open 
refrigerated units both having horizontal openings and generally vertical 
openings. In those cases where the refrigerated unit has been provided 
with a barrier over the access opening, typically swinging or sliding 
glass doors have been provided. 
The use of plastic or glass doors over refrigerated display openings has 
been limited due to the inconvenience of use, the high expense of 
installation, and high maintenance cost where such glass or plastic is 
subject to breakage, scratching, or discoloration. In many applications, 
such glass and plastic doors have provided only limited access to a 
portion of the refrigerated display unit or are cumbersome to open and 
remove merchandise from the refrigerated case in as much as such units 
typically incorporate a means for urging the heavy door back into the 
closed position. 
What is needed is an access barrier for use with refrigerated display units 
which is simple, rugged, economical, and which provides substantially free 
access into and out of the refrigerated unit while effectively isolating 
the interior of the refrigerated unit from the ambient environment. 
BRIEF SUMMARY OF THE INVENTION 
The present invention is an apparatus for forming a shield across an 
aperture across which a temperature gradient is maintained while still 
permitting substantially free access therethrough. The apparatus comprises 
a plurality of substantially transparent panels and a means for disposing 
the plurality of panels across the aperture and tensioning the plurality 
of panels. Each one of the plurality of panels is adjacent to at least one 
other one of the plurality of panels. By reason of this combination, a 
thermal barrier is formed across the aperture without substantially 
prohibiting free movement therethrough. 
The invention may further be characterized by the embodiment wherein each 
one of the plurality of panels assumes an abutting or overlapping 
relationship with at least one other one of the plurality of panels in at 
least one configuration. In another embodiment, each one of the plurality 
of panels may be resilient to facilitate access therethrough. 
The means for disposing the plurality of panels across the aperture and 
tensioning the plurality of panels may include a frame rigidly holding the 
opposing edge segments of each one of the plurality panels. In another 
embodiment this means may include a spring means for maintaining tension 
on the plurality of panels. In yet another embodiment this means may 
include a rotating means for permitting rotation for at least one edge 
segment of each one of the plurality of panels. 
The present invention and its various embodiments as set forth briefly and 
generally above can be better understood in connection with the following 
figures in light the detailed description of the preferred embodiments.

DETAILED OF THE PREFERRED EMBODIMENT 
The present invention is an access shield for thermally isolating an 
aperture in a refrigerated device from the ambient environment while 
permitting access through the aperture. The access shield comprises a 
plurality of resilient, substantially transparent panels. The plurality of 
panels have at least one configuration wherein each one of the panels is 
adjacent to and partially overlaps at least one other one of the panels. 
The apparatus further comprises a means for disposing a plurality of 
panels across the aperture and tensioning each one of the panels across 
the aperture. By reason of this combination of elements thermal energy 
flow across the aperture is reduced without prohibiting access across the 
aperture. The plurality of panels may also include at least one opening 
and typically a plurality of openings through the plurality of panels to 
permit a predetermined airflow through the opening and the panel array 
when in the normally closed configuration. 
The utility, and the manner in which the present invention may be 
fabricated and used, can be better understood by considering the following 
description in conjunction with the Figures. 
In FIG. 1, a typical refrigerated display device 10 is shown as having its 
upper, horizontal aperture 12 covered by an array 14 of panels fabricated 
according to the present invention. Typically, the panels are 
substantially transparent, such as a transparent plastic, thereby 
permitting the consumer to freely view the contents through refrigeration 
display device 10. Array 14 of panels substantially close aperture 12 
thereby reducing the amount of thermal energy lost across aperture 12 to 
the ambient environment. When the consumer desires to make a selection and 
remove an article from the interior of refrigerated display device 10 he 
merely thrusts his hand through array 14 and grasps the underlying 
article. The panels of array 14 will yield or give way and permit both the 
consumer's hands to be thrust inward to the interior of refrigerated 
display device 10 and to permit the withdrawal of even bulky articles, 
such as frozen turkeys, without substantial interference. The embodiment 
of the present invention particularly shown in FIG. 1 is better seen in 
plan view in FIG. 2. 
FIG. 2 illustrates one embodiment of a means for disposing the plurality of 
panels across aperture 12 of refrigerated display device 10 and tensioning 
the plurality of panels. As shown in FIG. 2 this means includes a frame 16 
which may be generally rectangular and typically made from extruded or 
rolled form aluminum, plastic or other compositions. Within frame 16 is a 
plurality of panels 18. In the embodiment illustrated, panels 18 are shown 
as having a generally rectangular shape, with a long or major axis many 
times greater than the shorter or minor axis. Throughout the specification 
the panels are shown as rectangular panels with straight edges. However, 
it must be understood that the panels may assume any geometric shape well 
known to the art including parallelograms, triangles, circles and even 
irregular shapes. Edges 20 of panels 18 need not be straight lines but may 
be curved, serrated, jagged, feathered or any configuration known to the 
art. 
Frame 16 is coupled to opposing edge segments 22 of each one of the 
plurality of panels 18. Frame 16 may also include resilient springs 24 on 
at least two adjacent edges of frame 16. Frame 16 will typically be 
mounted in a perimeter mating J-channel track which is coupled to 
refrigerated display device 10. Springs 24 will be compressed within the 
J-channel perimeter and to adjacent H-channel multi-track, thereby 
securing frame 16 across aperture 12 in a manner well known to the art. 
As shown in FIG. 2, panels 18 are disposed within frame 16 in an 
overlapping relationship. Each panel overlaps the next adjacent panel 
along at least a portion of the length of panel 18. Typically, the panel 
is made of a plastic material which has an inherent resiliency. When the 
consumer places his hand through the plane defined by panels 18, the 
panels will twist, stretch and deflect to permit the hand to move through 
substantially any point of array 14 of panels 18. Similarly, when the user 
withdraws his hand the natural resiliency of panels 18 will tend to bring 
the panels back into a substantially flat, sealing and/or overlapping 
relationship as shown in FIG. 2. Thus, array 14 of panels 18 form a 
thermal barrier which tends to maintain the temperature gradient across 
aperature 12 of refrigeration display device 10, and yet permits user 
access to the interior of refrigerated display device 10. 
As shown in FIG. 1 and as shown in greater clarity in FIG. 3, array 14 of 
panels 18 include a plurality of openings 26. In the embodiment 
illustrated in FIGS. 2 and 3, openings 26 are shown as disposed at the 
overlap between edges 20 on adjacent panels 18. Metal grommets 28 are 
fitted through the overlapping portion of both panels 18 and define 
opening 26. The size and number of grommets 28 are selected according to 
design principles well understood in the art to allow a predetermined 
amount of airflow through array 14 of panels 18, and to maintain positive, 
lateral tension between overlapping adjacent panels. Grommets 28 will 
permit airflow to prevent condensation which might otherwise be 
established because of the temperature gradient across array 14. Further, 
a limited amount of air circulation might be necessary in a refrigerated 
cabinet to avoid the accumulation of undesired odors or staleness. In the 
illustrated embodiment, grommets 28 are shown as disposed near edge 
segments 22 and thereby are substantially non-interfering with the 
separation of panels 18 along edges 20. Grommets 28 thus, also serve to 
aid as a mechanical fastener between adjacent panels 18. It is to be 
understood, however, that openings 26 may be disposed in array 14 in any 
manner desired according to well known design principles and that grommets 
28 may be eliminated and a wide number of equivalent types of fasteners 
substituted. 
FIG. 3 shows one way in which panels 18 may be fastened to frame 16. End 
segments 22 are disposed in a U-shaped channel 30 which may be formed as 
an integral part of an extruded aluminum frame 16. A resilient cord 32 
having longitudinally ribbed serrations is press-fit into U-channel 30 
over end segments 22 in a manner well known to the art. Cord 32 is well 
known in the screening industry and its dimensions, composition and design 
may be appropriately selected to optimize performance in the application 
in the present invention in view of the physical properties of panels 18 
and the temperatures at which frame 16 will be maintained. Cord 32 may be 
secured to frame 16 by insertion of rivet 34 through selected ones of end 
segments 22, cord 32 and U-channel 30. Cord 32 may be temporarily secured 
by substituting screws or other temporary fasteners in place of rivet 34. 
The means used to fasten end segments 22 to frame 16 is shown by way of 
example only and any other means known to the art may be employed or 
devised depending in part upon the structure of frame 16. 
FIG. 4 illustrates another embodiment of the present invention wherein 
array 14 of panels 18 are disposed across an aperture in combination with 
a tensioning device 36, such as a spring tensioned roller 38. In the 
embodiment illustrated in FIG. 4 panels 18 are overlapping in the manner 
as described in regard to the embodiment of FIGS. 2 and 3 but terminate or 
are coupled at one end to an end panel 40 and at the other end to a 
fixture 42. End panel 40 may likewise be coupled to a receiving fixture 46 
which in turn is attached to refrigerated display device 10. The manner of 
coupling end panel 40 to fixture 46 may be effected by any means well 
known to the art. Ends 48 of panels 18 may be coupled to end panel 40 by 
integral molding, adhesion, thermal bonding or by any other known means. 
Ends 50 of panels 18 are illustrated in FIG. 4 as terminating in a rail or 
fixture 52. Rail 52 is slidily disposed or otherwise temporarily coupled 
to a mating rail 54. Together, rails 52 and 54 comprise coupling fixture 
42. Mating rail 54 is coupled to a flexible end panel 56 which is 
typically of the same material as panels 18. End panel 56 in turn is 
coupled to roller 38 within tensioning device 36. The design and detail of 
tensioning device 36 is well known to the art and has been used in the 
window screening industry. The spring of tensioning device 36 is wound to 
a predetermined condition to maintain a selected amount of tension upon 
end panel 56. When fixture 46 is uncoupled from the refrigerated unit, the 
spring tension on roller 38 will tend to roll end panel 56 around roller 
38 thereby pulling array 14 upward into tensioning device 36. After end 
panel 56 has been wrapped around roller 38, coupling fixture 42, and more 
particularly, rail 54 will contact lips 58 of housing 60 of tensioning 
device 36. The relative dimension of the opening between lips 58 and rail 
54 are such that further withdrawal of end panel 56 around roller 38 is 
prohibited. At this point, that portion of array 14 below rail 52 is no 
longer under tension. The lower portion of array 14 may then be 
conveniently removed for replacement or repair. 
The embodiment of FIG. 4 will find particular adaptation in vertical 
refrigerated display cases having large apertures 12 which may not be 
conducive for use with large sized frames 16. The embodiment of FIG. 4 is 
also particularly useful to maintain a selected tension on panels 18 
inasmuch as end panel 56 is relatively short and the variation of tension 
on roller 38 is small between the fully extended and fully retracted 
configuration of end panel 56. Furthermore, the embodiment to FIG. 4 will 
automatically compensate for stretching and fatigue which may occur over 
time and with usage of array 14 to maintain sealing or closure of edges 20 
by spring tension. 
FIG. 5 shows yet another embodiment of the present invention wherein panels 
18 are arranged and configured in an overlapping relationship in a 
louvered type array to form a substantially flat shield. The array 
includes a plurality of resilient panels each having a fixture at each end 
of each panel to permit independent rotation of each end of the panel and 
to maintain a predetermined tension on each panel. As shown in FIG. 5 a 
means for tensioning and disposing panels 18 across aperture 12 may be 
comprised of a rotatable fixture 62. Panels 18 may extend on each side 
outwardly from fixture 62, thereby establishing an overlapping 
relationship with the adjacent panel. In addition to the inherent 
resiliency and twisting of panels 18, rotatable fixture 62 will increase 
the degree and ease of access through array 14 by permitting end segments 
22, held by rotatable fixture 62, to rotate. As described below, fixture 
62 is designed to assume a temporarily locked position wherein each of 
panels 18 will be held in alignment to the adjacent panels in an 
overlapping or abutting relationship to form the thermal barrier desired. 
The operation and structure of fixture 62 can be better understood by 
viewing FIGS. 6 and 7. In FIG. 6 one embodiment of fixture 62 is shown in 
exploded perspective view. Fixture 62 is comprised of a rotatable holder 
64 coupled to edge segment 22 of one of panels 18 and a receiving fixture 
70. Holder 64 has a center pivot hole 66 and at least one protrusion 68 
extending from holder 64. Protrusion 68 is off-set from pivot hole 66. 
Receiving fixture 70 is also provided with a pivot hole 66. Receiving 
fixture 70 has at least one indentation 72 for receiving protrusion 68. 
Rotatable fixture 64 also includes a spring-loaded pivot pin 74 which is 
disposed in pivot hole 66 in receiving fixture 70. Spring loaded-pivot pin 
74 tends to urge protrusion 68 into indentation 72 thereby temporarily 
locking rotatable fixture 64 in a selected position. Fixture 64 rotates 
freely when in a configuration other than the temporarily locked position 
by applying torsional force to panel 18 which tends to return it to the 
selected or temporarily locked position. The force of the user's hands and 
arms against edges 20 of panels 18 is sufficient to rotate fixture 64 from 
the temporarily locked position to a free-swinging position. Similarly, 
after withdrawal of the hands and arms of the user fixture 64 will rotate 
back to the locked position, thereby returning array 14 of panels 18 to a 
substantially flat and sealed array. 
Holder 64 in the particular embodiment illustrated in FIG. 6 is shown as 
being comprised of a clip 78 having an internal chamber 80 and a neck 82. 
Both chamber 80 and neck 82 are provided with a plurality of internal 
longitudinal indentations or ridges which form jaws which helped to grasp 
and secure the material of panel 18 when it is inserted into clip 78. The 
material of panel 18 may be wound about a cylinder with a tabbed or keyed 
end for use with an appropriate tool. When the desired amount of material 
has been withdrawn within clip 78 and the tension adjusted on panel 18, a 
clip retainer spring 84 may be disposed in groove 86 between neck 82 and 
chamber 80 of clip 78. Retainer spring 84 extends around the ends of clip 
78 to the opposite groove 86 and has a nipple 88 which is urged by the 
resiliency of retainer spring 84 into a locking hole 90 provided in groove 
86. Dimension 92 of retainer spring 84 is chosen such that when locked 
into hole 90, retainer spring 84 will squeeze neck 82 of clip 78 thereby 
causing the jaws of neck 82 and chamber 80 to bite into the material of 
panel 18. 
A wing member 94 is shown in FIG. 6 as mating in a recess 96 provided in 
the bottom of clip 78. Indentation 72, which is the female counterpart of 
protrusion 68, is formed in a nest member 98. Nest member 98 mates in a 
correspondingly shaped recess 100 formed in the upper portion of track 76 
in such a manner that travel along track 76 is permitted. Indentation 72, 
in the embodiment of FIG. 6, is shown as the double lobed, symmetric bow 
tie shape corresponding to protrusion 68 of wing member 94. In the 
illustrated embodiment, wing member 94 is provided with a double lobed 
protrusion 68 which is shaped in the form of a bow tie, with its center 
symmetrically disposed about pivot hole 66. Many other shapes for 
protrusion 68 may be used without departing from the spirit and scope of 
the present invention. For example, each lobe may be in the shape of a 
split, truncated tear. That portion of the tear shape nearest pivot hole 
66 has sufficient thickness or extension from the plane of wing member 94 
to prevent its displacement from indentation 72 in nest member 98. In 
other words, spring-loaded pivot pin 74 will be completely compressed 
before protrusion 68 can be rotated and completely displaced from 
indentation 72. This will prevent the complete displacement of protrusion 
68 from indentation 72 when the user's hand in contact with panel 18, 
causes wing member 94 to rotate with respect to nest member 98. Also as a 
result, the spring tension exerted on protrusion 68 from spring-loaded pin 
74 will tend to urge protrusion 68 back into a fully mating position 
within indentation 72. 
As shown in cross section in FIG. 7, spring-loaded post 74 is disposed 
through pivot hole 66 and clip 78, wing member 94, nest member 98 and 
track 76. As shown in FIG. 7 spring-loaded post 74 includes two mating 
members, screw 104 and post 102. An access hole 83 is provided at the 
appropriate point in neck 82 of clip 78 to permit a tool to be inserted 
therethrough for the purpose of tightening screw 104. The materials of 
holder 64 and receiving fixture 70 may be chosen according to well known 
principles to optimize the application according to temperature, usage and 
durability. For example, wing member 94 and nest member 98 may be composed 
of selflubricating Teflon to avoid problems of friction, corrosion, and 
durability which may otherwise occur if soft metal parts were employed. 
However, it must be understood that the particular embodiment of FIGS. 6 
and 7 are shown only for the purposes of example, and other forms of 
fixture 62 may be employed within the scope and spirit of the present 
invention, such as using an integrally molded holder 64 and receiving 
fixture 70. 
FIG. 8 is a cross sectional illustration of another embodiment of fixture 
62. Embodiment of FIG. 8 differs from that of FIGS. 6 and 7 in that panel 
18 is coupled to a cuff 63. Cuff 63 may be an integral molded piece having 
lower flanges 65 and upper flanges 67. Panel 18 is inserted into the space 
between sides 69 of cuff 63, may extend laterally beyond the edges of 
sides 69 and may be bonded, fixed or coupled to cuff 63 by any means well 
known to the art, such as, adhesive bonds, thermal bonding, or mechanical 
riveting. Cuff 63 is disposed in a clip 71 having a slot 73 through which 
sides 69 extend. A cuff spring 75 is disposed within clip 71 and provides 
a compressive spring force between the points of contact between spring 75 
and lower flanges 65 of collar 63 and an upper flange 77 of clip 71. 
Spring 75 may be fixed or coupled to flange 77 by any well known means, 
such as riveting. This configuration allows cuff 63 to be extended 
upwardly in clip 71 by tension exerted upon panel 18. Spring 75 will urge 
cuff 63 downwardly into clip 71 thereby maintaining a predetermined amount 
of tension on panel 18. The opposite end segment 22 of panel 18 is 
provided with a similar apparatus and the tension exerted upon panel 18 
tends to keep both opposing end segments 22 aligned, one with the other. 
Clip 71 is also provided with a wing member 94 and nest member 98 of the 
type previously described. The fixture is coupled to track 76 by a pivot 
pin 74 which includes a screw 104 through clip 71 and post 102. In 
addition, a post sleeve 79 is disposed about post 102. Post sleeve 79 is 
provided with a reduced neck portion 81 described in greater detail below. 
Pivot pin 74 is spring loaded as described above by a coil spring 83, but 
also includes a washer or post spring saucer 85 disposed between spring 83 
and lower surface of track 76 which saucer 58 allows post 102 to be 
slidingly translated along the bottom of track 76. 
FIG. 10 illustrates in plan view, a nest member 98 disposed in recess 100 
of track 76. Shown partially in phantom outline below and extending to 
each side of nest member 98 is a slotted raceway 89. Raceway 89 is 
symmetric about pivot hole 66 which is formed in the middle of raceway 89. 
A spring 91 is coupled between a hook or similar means at one end of nest 
member 98 and a punched-out tab 95 or similar means in track 76. The 
opposing end of nest number 98 is provided with a similar spring. When in 
the equilibrium position, the opposing springs center nest member 98 about 
pivot hole 66 in slotted raceway 89. 
As best illustrated in FIG. 8, post sleeve 79 is in a first position when 
wing member 94 is in a configuration in which it fully mates with nest 
member 98. In this first position, post sleeve 79 has an upper portion 87 
extending through pivot hole 66. The diameter of upper portion 87 is 
chosen such that sufficient clearance is provided for free rotation in 
pivot hole 66 but any movement along slotted raceway 89 is prohibited. 
When wing member 94 is rotated with respect to nest member 98, spring 83 
will be compressed as wing member 94 rides upward and outward from the 
fully mating position within nest member 98. This will pull post 102 
upwardly through pivot hole 66 together with post sleeve 79. After a 
predetermined degree of rotation, post sleeve 79 will have been drawn far 
enough upward to place neck portion 81 in pivot hole 66. The outer 
diameter of neck portion 81 is such that post sleeve 81 may freely slide 
along slotted raceway 89. Sufficient clearance is provided between nest 
member 98 and recess 100 to permit free displacement of nest member 98 
when in this second position. Springs 91 will tend to urge nest member 98 
back to the equilibrium position wherein post sleeve 81 is aligned with 
pivot hole 66. Thus, after a predetermined degree of rotation has 
occurred, the fixture of FIGS. 8, 9 and 10 may also be translated along 
slotted raceway 89 in either direction to permit further opening between 
panels 18. This embodiment, then, has a four-fold action. Firstly, a 
natural and inherent resiliency of panels 18 permit a certain degree of 
stretching, twisting and bending to facilitate access of a user's hand and 
arms between adjacent panels. Secondly, spring loaded cuff 63 will provide 
additional resiliency to panel 18 to further facilitate access through the 
panel separations. Thirdly, wing member 94 and nest member 98 in 
conjunction with each of the other elements of the fixture will permit 
rotation, as described above, to allow end segments 22 of panels 18 to be 
rotated to even further facilitate access through the panel array. 
Finally, the combination of each of the above described elements with post 
sleeve 81 and slotted raceway 89 permits end segments 22 of each panel to 
displaced in either direction to maximize the separation between panels 
and to allow free access without substantial inhibition. The embodiment of 
FIGS. 8, 9 and 10, after use, will resume their equilibrium position 
thereby restoring array 14 of panels 18 to a substantially flat, sealing 
and/or overlapping relationship to form a thermal barrier across aperture 
12. 
Although the present invention has been described in connection with the 
particular embodiments of FIGS. 1 through 10, it is to be understood that 
many other alterations and modification may be made by those having 
ordinary skill in the art without departing from the spirit and scope of 
the present invention. What has been described is an apparatus for 
reducing the electrical consumption primarily but not limited to 
supermarket refrigerated displays. It is also expected that the present 
invention will extend the life of refrigeration equipment, such as motors, 
generators and compressors as well as decreasing maintenance required on 
the same. Refrigerated units, incorporating the present invention by 
design, may also be built with smaller refrigeration capacities and 
therefore may be built in a more economical manner. In addition, 
advantages are obtained with respect to space airconditioning and heating 
in markets employing a large number of open display refrigerated devices. 
It will no longer be necessary to heat the market's air space due to the 
large heat sinks formed by the open refrigerated display cases. In 
addition, with the more uniformly maintained temperature within the 
refrigerated devices, which the present invention will allow, it is also 
expected that the shelf-life of refrigerated food stuffs will be extended. 
The degree of consumer comfort will also be increased in the proximity of 
a large number of refrigerated display devices thereby permitting the 
consumer to view the merchandise without subjecting himself to a locally 
cold environment.