Contaminant shield and method of constructing same

A contaminant shield prevents airborne contaminants from contacting manufactured parts in a work area in a manufacturing facility. The contaminant shield is formed of a plurality of like frames, each formed of a plurality of interconnected side frame members covered by a flexible sheet attached at its outer edges to the side frame members. The frames are interconnected at adjacent edges to form the complete contaminant shield. A sealing strip is applied to the joints between adjacent frames to form a continuous contaminant barrier in conjunction with the flexible sheet attached to each frame. The contaminant shield is constructed by first constructing a plurality of frames by interconnecting side frame members into a rigid, planar frame and attaching the edges of a flexible sheet to each side frame member of the frame. Each of the side frame members includes an aperture which receives a complimentrally shaped cap which traps the edges of the flexible sheet between itself and the aperture in the side frame for securely attaching the flexible sheet to the side frame.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to building structures. 
2. Description of the Prior Art 
In manufacturing facilities, it is commonplace to protect parts and 
assemblies during manufacturing from airborne contaminants, such as dust, 
particles, water, etc., so as to prevent such contaminants from contacting 
the parts during assembly or during idle downtime. This is particularly 
important in painting, spraying and coating operations which require 
extreme cleanliness of the prepared surface before painting, etc., and 
protection of the painted surface until the paint has completely dried. 
To accomplish this, it is common to surround painting and spraying areas in 
a manufacturing facility with an enclosure to retain airborne paint 
particles within the enclosure and to prevent other contaminants from 
contacting the part surfaces. Such enclosures typically incorporate a 
skeletal framework of spaced, interconnected members to which a number of 
frame panels, typically rigid members made of steel or other material, are 
mounted. 
While the use of such a building structure is effective at containing the 
airborne particles within a given area or protecting parts from airborne 
contaminants, the cost of such a rigid panel enclosure is high especially 
since long distances must be covered and considerable installation time is 
required to install the framework in the manufacturing facility and to 
attach the rigid panels thereto. The high cost of previously devised 
enclosures has prevented their use over large portions of conveyor lines 
in manufacturing plants and, thus, the parts are left unprotected after 
painting, spraying, coating, etc., and between initial surface preparation 
and painting etc., and are vulnerable to dust, water and other airborne 
contaminants. 
Building structures have also been designed for other applications, such as 
greenhouses, tents, etc., which use a single, flexible sheet or cover 
which is placed over and attached to a skelatal framework. This building 
structure also forms an effective containment shield or barrier 
surrounding a given area. However, it has been found that it is difficult 
and time consuming to install a large, single piece cover to a large 
skeletal framework. This increases installation time and adds to overall 
manufacturing costs. 
Thus, it would be desirable to provide a containment shield which can be 
installed at the use site in a minimum amount of time. It would also be 
desirable to provide a contaminant shield which has reduced manufacturing 
costs. It would also be desirable to provide a contaminant shield which 
does not require a skeletal framework to be installed at the use site for 
attachment of rigid frame panels thereto. Finally, it would be desirable 
to provide a contaminant shield which can be constructed in any 
configuration for widespread use in many different applications. 
SUMMARY OF THE INVENTION 
The present invention is a contaminant shield and method of constructing 
the same. 
The contaminant shield of the present invention is formed of a plurality of 
identically constructed frames of the same or substantially the same 
configuration which are interconnected in a predetermined configuration to 
surround or cover a work area to prevent dust and other airborne 
contaminants or particles from contacting parts within the area. The 
frames are formed of a plurality of side frame members which are joined 
together into an integal, planar assembly having a predetermined shape. 
The side frame members surround an interior opening. A flexible sheet is 
attached to the side frame members covering the opening in the frame. 
A plurality of such frames, having the same or different configuration are 
interconnected together to form a contaminant shield having any desired 
shape. For example, a plurality of frame members may be interconnected to 
form a three-sided floor-mounted enclosure having opposed side walls 
joined together by a top. Similarly, the frame members may be joined 
together to form an elongated planar cover having depending side walls 
which covers a work area in a manufacturing facility. 
In one embodiment, means for attaching the edges of a flexible sheet to the 
side frame members of a frame are provided. Preferably, the attaching 
means comprises each side frame member having opposed side walls joined 
together at one end by an integral, central portion. The opposite ends of 
the side walls are each formed with an inwardly and downwardly extending 
flange, with the inner faces of the flanges being spaced apart to define 
an aperture opening into the hollow interior of each side frame member. A 
cap member has first and second end portions, with the first end portion 
being complimentary shaped to the configuration of the aperture in the 
side frame members. The second end portion of the cap member has an 
enlarged cross section with flanges extending outward from the first end 
portion. The first end portion of a cap member is slidably inserted into 
the aperture in a side frame member to trap an edge of the flexible sheet 
between first end portion and the side frame member to securely attach the 
flexible sheet to the side frame member. Cap members are inserted into the 
remaining side frame members of a frame to securely attach the sheet to 
the frame. 
After the frames are constructed at the manufacturing facility, they are 
shipped to the use site and arranged to form a contaminant shield having a 
predetermined configuration. After the frames are joined together as 
described above to form an enclosure, shield, cover, etc., the joints 
between adjacent side frame members of adjacent frames are sealed by a 
tape, for example, to provide a continuous, protrusion free surface in 
conjunction with the flexible sheet which provides no dust collection 
surfaces within or under the contaminant shield and effectively blocks the 
interior space enclosed or covered by the contaminant shield from airborne 
contaminants, such as particles, dust, water, etc. 
In a preferred embodiment, each of the side frame members has opposed side 
walls interconnected by a central portion. In attaching the flexible sheet 
to the frame according to the method of the present invention, the 
flexible sheet is first loosely placed over one entire side of the frame 
covering all of the side frame members. Tension is applied to one edge of 
the flexible sheet while the cap member is slidably inserted into one of 
the side frame members trapping the edge of the flexible sheet between 
itself and the side frame member. In a preferred embodiment, tensioning 
means in the form of an elongated rod is placed over the flexible sheet 
drawing one edge of the sheet into the hollow interior of the side frame 
member. This applies tension to the sheet while the cap is inserted into 
that particular side frame member. Similar steps are performed with the 
remaining side frame members of the frame until the cap members have been 
emplaced within each side frame member to securely attach all of the edges 
of the flexible sheet to the frame. 
The contaminant shield of the present invention provides many unique 
advantages in constructing contaminant shields or barriers for 
manufacturing facilties since it minimizes installation time and has a 
reduced manufacturing cost. By constructing the individual frames at the 
frame manufacturing site, the need for constructing and installing a 
skeletal frame at the use site is eliminated. This reduces installation 
time. Also, the advantages of mass production of identical or nearly 
identical frames is attained thereby reducing the overall manufacturing 
cost of the contaminant shield. Since the contaminant shield of the 
present invention finds advantageous use with conveyor lines or other 
elongated work areas, the contaminant shield will contain a large number 
of identical frames thereby enabling the economies of mass production of 
the identical modular frames at the frame manufacturing site to be 
realized. 
The contaminant shield of the present invention, once installed at the use 
site, provides an effective barrier which prevents airborne contaminants, 
such as dust, particles, waterm etc., from contacting work parts or 
assemblies in a given area within a manufacturing facility.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Throughout the following description and drawing, an identical reference 
number is used to refer to the same component shown in multiple figures of 
the drawing. 
As shown in general in FIG. 1, the present invention is a contaminant 
shield 10 which protects manufacturing parts and assemblies in a 
predetermined area in a manufacturing facility from contact with airborne 
cotaminants, such as dust particles, etc., during the manufacturing 
process. 
As shown in FIG. 1 and in greater detail in FIGS. 2-5, the contaminant 
shield 10 may be formed in any desired configuration having any 
predetermined length, width, height or shape depending upon the particular 
application to which it is applied. By way of example only, the 
contaminant shield 10 shown in FIG. 1 is in the form of a three-sided 
enclosure having opposed open ends through which parts pass. 
The contaminant shield 10 is formed of a plurality of interconnected frames 
12. The frames 12 may have any desired shape or configuration, such as 
square, rectangular, triangular, trapezoidal, etc., as required for a 
particular application. The frames 12 may also have any desired 
dimensions. For reasons of clarity, the following description will be 
provided for a general overall description of the construction and use of 
the frame 12 shown in FIG. 1. It will be understood that this is general 
in nature and is not intended to limited applicant's invention to the 
specific configuration shown in FIG. 1. 
As shown in FIGS. 2, 3 and 4, each frame 12 includes a plurality of side 
frame members 14, 16, 18 and 20 which are joined together at their ends 
and covered by a flexible sheet 22. The side frame members 14, 16, 18 and 
20 are joined together, typically by welding, at their abutting ends as 
shown in FIG. 2. The side frame members thus form an opening between their 
innermost edges which is covered by the flexible sheet 22. 
In a preferred embodiment, the flexible sheet 22 is attached to the frame 
12 by attaching means. The attaching means includes each of the side frame 
members 14, 16, 18 and 20 being formed with opposed side walls 24 and 26, 
as shown in FIG. 3, which are interconnected at one end by a central bite 
portion 28. The opposed ends of the side walls 24 and 26 terminate in 
inwardly and downwardly extending flanges 30 and 32, respectively, which 
define an aperture 33 between their opposed, facing surfaces. The aperture 
33 opens into the hollow interior 34 within the side frame member, such as 
side frame member 20 shown in FIG. 3. 
The attaching means also includes a cap 36 which is removably insertable 
into the aperture 33 formed between the flanges 30 and 32 to trap and 
securely attach the edges of the flexible sheet 22 to the side frame 
member 20. As shown in detail in FIG. 3, the cap member 36 has a first end 
portion formed of spaced flanges 38 and 39 which are spaced apart so as to 
snugly engage the flanges 30 and 32 in the side frame member 20. The 
second end portion 40 of the cap 36 has an enlarged cross section with 
outwardly extending flanges 42 which overlie the edges bounding the 
aperture 33 to form a substantially smooth continuous surface with the 
flexible sheet 22. 
As shown in FIGS. 2 and 4, a plurality of generally U-shaped clamps 44 are 
inserted over the top of the cap members 36 and adjoining side edges of 
the side frame member, to hold the cap member 36 in place in the side 
frame member. One end 45 of the clamp 44 is bent toward the opposed leg to 
enable it to securely engage and exert a downward pressure on the cap 
member 36. This is important in certain applications since the flexible 
sheet 22 has a tendency to shrink at elevated temperatures thereby placing 
tension on the cap members 36 which could cause inadvertent release of the 
cap member 36 from the side frame member. 
Various reinforcing members may also be employed to increase the rigidity 
and structural strength of the frame 12. As shwon in FIGS. 1 and 2, a 
reinforcing strip 46 having a form substantially identical to that of the 
side frame members 14, 16, 18 and 20 is connected at opposed ends between 
two of the opposed side frame members, such as side frame members 16 and 
20 as shown in FIG. 2. Further, additional reinforcement members 48 and 50 
may be connected as shown in FIG. 1 between the reinforcing strip 46 and 
one of the side frame members, such as side frame member 14, for futher 
rigidity. It should be noted that the additional reinforcing members 48 
and 50 need not be employed in each frame in the complete contaminant 
shield 10 but only at spaced locations along the length of the shield 10 
where needed. 
The flexible sheet 22 is preferably formed of a flexible material which has 
sufficient strength to resist tearing or ripping and yet provides a non 
air porous barrier which prevents the passage of airborne contaminants 
through the contaminant shield 10. Preferably, the flexible sheet 22 is 
formed of a flexible, plastic material which is clear or at least 
semi-transparent. 
Referring now to FIG. 4, there is illustrated the sequential method steps 
employed in forming one of the frames 12 of the present invention. The 
first step in forming the frame 12 is to interconnect a plurality of side 
frame members, such as side frame members 14, 16, 18 and 20 in the example 
shown in FIG. 4, into a planar shape. A rectangular shape is illustrated 
in FIG. 4 by way of example only and includes four side frame members 14, 
16, 18 and 20 which are joined together at their ends by any suitable 
means, such as by welding. Next, after the side frame members 14, 16, 18 
and 20 have been joined together, the flexible sheet 22 is placed 
thereover and attached to the side frame members 14, 16, 18 and 20. 
In a preferred embodiment, attaching means is employed which comprises the 
interfitting cap members 36 which are slidably insertable into the hollow 
interior 34 of each of the side frame members as described above. It is 
also preferred that tension be applied to the flexible sheet 22 as each 
cap member 36 is inserted into its associated side frame member. 
Accordingly, tensioning means 52 in the form of a heavy, elongated rod is 
utilized. The rod 52 is placed over one edge of the flexible sheet 22 
drawing the one edge of the flexible sheet 22 into the hollow interior 34 
of one side frame member, such as side frame member 14. This applies 
tension to one end of the flexible sheet 22 as the cap member 36 is 
inserted into the side frame member 14. The tensioning rod 52 is then be 
removed from the side frame member 14. 
Another tensioning rod 52 is inserted over the flexible sheet 22 at the 
opposed end of the frame 12 drawing the opposite end of the flexible sheet 
22 into the hollow interior 34 of the opposed side frame member 18 as 
shown in FIG. 4. This applies tension along one dimension of the flexible 
sheet 22 as the cap member 36 is inserted into the side frame member 18. 
The second tensioning rod 52 is then be removed from the side frame member 
18. 
The cap members 36 are then inserted into the remaining side frame members 
16 and 20 as tension is applied to the edges of the flexible sheet 22 
overlaying each side frame member 16 and 20. Such tension can be applied 
by manually pulling on the outer edge of the flexible sheet 22 as each cap 
member 36 is inserted into the side frame member 16 and 20. 
Finally, the cap clamps 44 are attached over the caps 36 to provide secure 
retention of the caps 36 in the side frame members. 
As noted above, advantageous use of the present invention may be attained 
by first constructing a plurality of frames 12 ad described above at a 
frame manufacturing facility and then shipping the frames 12 to the use 
site for interconnection into the completed contaminant shield 10. Since 
the contaminant shield 10 will usually incorporate a large number of 
identical frames 12, the advantages of large scale mass production may be 
realized since a large number of identical frames 12 may be constructed at 
one time at the manufacturing site. 
The interconnection of the frames 12 into the complete contaminant shield 
10 is illustrated in greater detail in FIG. 5 which depicts the 
interconnection of two adjacent, vertically oriented frames, denoted in 
general by reference numbers 54 and 56, with a top frame 58 to form the 
contaminant shield 10 shown in FIG. 1. 
Each of the frames 54, 56 and 58 is substantially identically constructed 
as described above and shown in FIGS. 2, 3 and 4. The vertically oriented 
frames 54 and 56 may be attached to an underlying support surface, such as 
the floor or be free standing. The two vertically oriented frames 54 and 
56 are abutted, side-by-side and may be optionally aligned by means of an 
interconnecting plug 60. The plug 60 has a cross section so as to enable 
it to slidably fit within the hollow interior of the uppermost side frame 
members forming the frames 54 and 56 as shown in FIG. 5. Apertures for 
receiving fasteners, not shown, are formed in the interconnecting plug 60 
and the cental portions of the side frame members of the frames 54 and 56 
to secure adjacent disposed frames 54 and 56 together. 
Interconnection is also provided for attaching one or more top, 
horizontally oriented frames 58 to one or more vertically oriented frames 
54 and 56. A planar connector 62 includes apertures 64 which are alignable 
with corresponding apertures 66 formed in the side frame members of the 
vertically oriented frames 54 and 56 to receive fasteners to securely 
attach the horizontal frame 58 to the vertical frames 54 and 56. 
Additional planar connectors, not shown, may also be employed along the 
vertical extent of the frams 54 and 56 to securely joint adjacent side 
frame members together into an integral unit. 
In order to provide a contaminant free barrier as well as a shield having 
no dust or contaminant collection surfaces, it is preferred that the 
flexible sheet 22 be disposed on the inward side of the contaminant 
shield, as shown in FIG. 1, on the vertically oriented frames and on the 
inward or outward facing side of the horizontally oriented frames, such as 
frame 58. In this manner, any contaminants or particles which may enter 
the interior of the contaminant shield 10 will fall directly to the floor 
and will not adhere to the vertical or horizontal surfaces of the 
contaminant shield 10. 
Sealing means is also employed to completely seal the joints between 
abutting side frame members of adjacent positioned frames. This is shown 
in FIG. 5 by means of a sealing strip or tape 70 which is placed over the 
joint between adjacent side frame members 16 and 20 of side frames 56 and 
54, respectively. The sealing strip 70 may be placed on the side of the 
joint between the flexible sheets 22 on the side frames 56 and 54 or on 
the opposite side as desired. This provides a continuous barrier 
preventing the passage of contaminants through the contaminant shield 10. 
As noted above, the contaminant shield 10 of the present invention may be 
formed in any desired configuration depending on the particular 
application to which it is applied. As shown in FIG. 1, additional 
reinforcements, such as angularly positioned bars 72 may be attached 
between vertically extending side frame members and horizontal side frame 
members of interconnected frames to provide structural rigidity for the 
overall contaminant shield 10. 
Also, certain applications require a sloped or angled top cover for water 
drainage. This requirement can be achieved by merely forming certain side 
frame members, such as side frame members 16, 20 in the orientation shown 
in FIG. 1, with a longer length than the corresponding side frame members 
of opposed frames. This will cause the top positioned frame to be disposed 
at a downward extending angle from one side of the shield 10 to the other. 
Alternately, the top most frame can be formed in two or more angularly 
disposed sections which angle downward from a peak. 
Further, a frame may be constructed having a slidable door, such as 
slidable door 74 mounted in frame 76 in FIG. 1. The door 74 and frame 76 
are formed substantially identical to that described above with respect to 
frame 12 including the side frame members and overlying, attached flexible 
sheet 22. However, the door 74 is provided with its own frame and flexible 
sheet 22 and includes rollers 78 which slide within a track 80 mounted on 
the frame 76. The door 74 is sized to fit in approximately one-half of the 
width of the frame 76, with the remaining half having a flexible sheet and 
side frame assembly constructed identical to that described above for 
frame 12. The door 74 allows access to the interior of the contaminant 
shield 10 which may be desirable in certain applications where the length 
of the contaminant shield 10 is considerable. It should be noted that a 
plurality of doors 74 may be employed at spaced intervals along the length 
of the contaminant shield 10 where access is desired to the interior of 
the contaminant shield 10. 
An alternate configuration for the contaminant shield of the present 
invention is shown in FIG. 6. In FIG. 6, the contaminant shield 82 is in 
the form of a cover overlying a work surface. The cover is not attached to 
the floor; but, rather, is attached to the overhead building support or 
frame work structure. The contaminant shield 82 is formed with two 
identical sections 84 and 86, each including a top, substantially 
horizontally oriented portion 88 and attached depending side walls 90. 
Both the top portion 88 and the depending side wall portions 90 are formed 
of a plurality of interconnected frames, formed identical to that 
described above with reference to frame 12. 
It should be noted that the top portions 88 of the sections 84 and 86 are 
spaced apart leaving an opening 92 extending along the length of the 
contaminant shield 82 for passage of a conveyor 94 for conveying parts 
through the contaminant shield 82. The depending side wall portions 90 are 
interconnected and attached to one edge of the top sections 88 by means of 
angularly shaped connectors 96 which are attached to the side frame 
members of the top and side wall sections 88 and 90 by means of suitable 
fasteners, such as bolts, screws, etc. It should be noted that the side 
walls 90 may be disposed at any desired angle with respect to the top 
portion 88. Also, the top portions 88 may be disposed at a downward angle 
with respect to the horizontal to provide a sloped shape for the shield 82 
for water drainage. 
In summary, there has been disclosed a unique contaminant shield and method 
for constructing the same which prevents airborne contaminants, such as 
dust particles, water, etc., from contacting and accumulating on the 
surfaces of parts and assemblies in a manufacturing facility. The 
contaminant shield is formed of a plurality of identically constructed 
modular frames having a flexible sheet attached to each frame. The frames 
are interconnected at the manufacturing site to form the complete 
contaminent shield thereby reducing installlation time since a skeletal 
frame work is not required and the economies of mass production of large 
numbers of substantially identical frames may be realized at the frame 
manufacturing site.