Fabric/rail attachment process

Abstract

A channel which extends along a periphery of a panel member is initially provided on at least part of an inner wall thereof with a thin coating of a solid but tacky material which provides a high friction gripping surface. An edge portion of a fabric sheet, which covers a side face of the panel member, is engaged with the tacky coating and retained in the groove by a deformable retainer. The coating is preferably applied to an inner wall of the channel as a liquid, and is distributed over a greater area of the channel wall by an air nozzle which spreads out the material so that it not only extends lengthwise along the channel but also transversely over a significant width, thereby creating a significant contact area for gripping engagement with the edge portion of the fabric when the deformable retainer is inserted in the groove.

Description

FIELD OF THE INVENTION

This invention relates to an improved process for securing a large flexible covering sheet, such as a fabric sheet, to a peripheral edge of a large panel-like member so that the sheet extends tautly over a side surface of the panel-like member.

BACKGROUND OF THE INVENTION

Upright space-dividing wall panels are conventionally utilized in offices and the like for dividing large workspaces into smaller work areas. The wall panels are conventionally in the range of one foot to five feet wide, sometimes wider, and have a height which varies approximately from desk height to ceiling height. These panels typically have one or both of the opposite side faces covered by flexible covering sheets such as fabric sheets which are stretched across the panel faces and secured along the panel boundaries or edges. The securement of the covering fabric along the panel edges is conventionally accomplished by several known techniques, most of which employ some type of gripping member for holding the fabric edge to maintain the fabric in a stretched or taut condition as it extends across the panel side face.

In one conventional securing technique, the panel is provided with an outwardly opening retaining channel along each edge thereof. The retaining channel is configured to permit an edge portion of the flexible covering sheet to be folded therein, and a retaining member (sometimes referred to as a spline), such as an elongate compressible band or similar such element, is inserted into the retaining channel to effect gripping of the edge portion of the covering sheet between the deformed retaining member and the side wall of the retaining channel, thereby holding the covering sheet in a stretched or taut condition. Arrangements of this type for securing a flexible covering sheet or fabric to the side face of panel members are well known, and examples of such constructions are disclosed in U.S. Pat. Nos. 4,213,493, 4,891,922 and 5,377,466, all owned by the Assignee hereof.

The fabric securement arrangement summarized above has been widely utilized and has generally performed in a highly successful manner with respect to permitting covering sheets to be assembled to panel members in a stretched condition, while at the same time permitting the covering sheet to be removed and replaced if necessary or desired. However, it has been observed that the physical properties of some flexible covering sheets, specifically fabric sheets which are either extremely thin or have a shiny or slippery surface characteristic, are more difficult to secure and maintain taut when using a retaining arrangement of the above-described type.

Accordingly, it is an object of this invention to provide an improved fabric retaining process for use with panel members so as to provide an improved panel member having a flexible covering sheet stretched tautly across a side face thereof, which improved fabric retention process continues to utilize a deformable bead or spline inserted into an edge channel of the panel member for securing an edge portion of the covering sheet therein, but which provides improved frictional gripping of the covering sheet so as to provide desirable performance for a wider range of covering sheet materials, including thin, slippery and sheer fabrics.

In the improved fabric retention process and apparatus of the present invention, the channel which extends along the periphery of the panel member and which accommodates the edge portion of the fabric as well as the deformable retaining bead, is initially provided on at least part of an inner wall thereof with a thin coating of a solidified but tacky material which provides the wall of the channel with a high friction gripping surface. This material directly engages the edge portion of the fabric sheet which is retained in the groove by the deformable bead and hence creates significantly improved gripping engagement with the fabric sheet, including fabric sheets which are of thin or slippery material, to enable the fabric covering sheet to be properly stretched across the face of the panel member and maintained in a taut condition. The coating material, however, even though it retains a tacky-feeling surface which provides a high friction, nevertheless is solid (i.e. a solidified material) and does not adhere to the fabric, and in fact readily permits the fabric to be removed from the channel when replacement of the fabric is necessary or desired.

In the process of the present invention, the coating material is preferably applied in a liquid state to an inner wall of the channel, preferably the outer leg of the channel, and is distributed over a greater area of the inner channel wall by an air nozzle which spreads out the material so that it not only extends lengthwise along the channel but also transversely over a significant width so as to create a significant contact area for gripping engagement with the edge portion of the fabric when the deformable retaining member is inserted. The edge portion of the fabric hence becomes securely retained between the deformable retaining member and the coating on the channel wall.

Other objects and purposes of the present invention, and advantages resulting therefrom, will be apparent upon reading the following specification and inspecting the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view which illustrates an upright wall panel system employing wall panels having fabric sheets stretched across the exterior side faces thereof.

FIG. 2 is an enlarged fragmentary cross-sectional view taken along one edge of a conventional panel member and showing the construction thereof.

FIG. 3 is a cross-sectional view of solely the edge rail associated with the panel shown in FIG. 2.

FIG. 4 is a diagrammatic view which illustrates the process and apparatus of the present invention for creating a high-friction coating on an inner wall of the fabric-retaining channel associated with the panel edge rail.

FIG. 5 is an enlarged transverse cross section of the panel edge rail and showing the application of beads of coating material to the gripping channels thereof according to the present invention.

FIG. 6 is a view similar to FIG. 5 but showing the beads of coating material spread out and dried so as to create a thin coating over at least a part of the wall defining the gripping channel for the fabric edge.

FIG. 7 is a view similar to FIG. 6 but showing the securement of the fabric edge within the gripping channel.

Certain terminology will be used in the following description for convenience in reference only, and will not be limiting. For example, the words “upwardly”, “downwardly”, “rightwardly” and “leftwardly” will refer to directions in the drawings to which reference is made. The words “inwardly” and “outwardly” will refer to directions toward and away from, respectively, the geometric center of the arrangement and designated parts thereof. Said terminology will include the words specifically mentioned, derivatives thereof, and words of similar import.

DETAILED DESCRIPTION

Referring to FIG. 1, there is illustrated a known upright space-dividing wall system 10 formed by a plurality of upright space-dividing wall panels 11 joined together in a series arrangement to define an upright wall used for space-dividing purposes. Such wall panels and their use are conventional and well known, and reference is made to U.S. Pat. No. 5,377,476 for additional detail relative thereto.

The panel assembly 11 includes a generally rigid ring-shaped frame 12 which is generally of rectangular configuration and is defined by an opposed pair of generally parallel and elongated edge frame members or rails 13, such as horizontally extending top and bottom frame rails, which are rigidly joined together by a pair of generally parallel elongate edge frame members or rails 14 which typically extend vertically along opposite sides of the frame. The horizontal and vertical rails 13 and 14 are normally either identical or extremely similar in cross section, depending on whatever additional functional parameters are associated with the specific edge rail.

The interior of the panel frame is, as illustrated by FIG. 2, normally occupied by a core structure of conventional construction. In the illustrated embodiment, the core structure within the frame includes an inner or centrally positioned paper honeycomb layer 16 which is sandwiched between a pair of side sheets or panels 17, the latter in the illustrated embodiment being of a construction similar to fiber or mineral board, although numerous other conventional materials can be utilized. The side boards 17 in turn are covered by large sheets of a thin flexible covering material 19, typically a thin sheetlike fabric, which extends coextensively over the exterior or outer side face 18, with the edges of the fabric covering sheet 19 being appropriately secured to the edge rails 13 and 14 so as to define the side peripheral edges of the wall panel assembly. A thin layer of fiberglass or similar sound absorbing and/or cushioning material is also typically interposed between the side boards 17 and the overlying fabric covering sheets 19.

The frame rails 13, 14, as illustrated by FIGS. 2 and 3, are preferably transversely dimensioned to extend across substantially the full width of the panel assembly, and each includes a center web structure 21 which is fixedly joined to a pair of generally U-shaped parts 22 disposed adjacent opposite sides of the panel so as to extend along each panel edge. The U-shaped parts are generally disposed substantially symmetrically on opposite sides of a central vertical plane 23 of the panel. Each U-shaped part 22 defines therein an outwardly opening channel or groove 24 which is elongated throughout the entire length of the respective frame rail. The channels or grooves 24 associated with the same rail both open generally outwardly away from the interior of the panel and generally outwardly away from one of the elongated dimensions of the panel. In the illustrated embodiment the pair of grooves 24 associated with the rail open outwardly in the same direction and in generally parallel relationship with one another.

Each of the channel parts 22 is defined generally by opposed inner and outer legs or walls 26 and 27 respectively, which in the illustrated arrangement extend approximately parallel with one another, and which are joined by a rounded bottom or base wall 28 which closes off the bottom of the respective channel or groove 24. The outer wall 27, adjacent the mouth or open side of the channel 24, is typically provided with a convexly rounded or radiused corner 29 which bends outwardly away from the channel.

As illustrated by FIG. 2, the flexible fabric sheet 19 which covers the side face of the panel assembly is oversized relative to the side face so that the flexible fabric covering sheet defines thereon an edge portion 41 which can be folded over onto itself and inserted into the channel 24 which extends lengthwise along the respective edge of the panel assembly. A conventional retainer member or spline 42 is then inserted into the channel 24 between the overlapping layers of the folded fabric edge portion 41, with the size of the channel and the retainer 42 and the thickness of the associated fabric, being such that the retainer 42 which extends lengthwise of the channel 24 is suitably sidewardly compressed or deformed so that the overlapping layers of the fabric edge portion 41 hence become clampingly gripped between the deformed retainer 42 and the opposed respective inner or outer channel wall 26 and 27, respectively. The retainer 42 may be of any suitable deformable material, conventionally an elastic material such as rubber or elastomer, so as to facilitate the insertion into the groove and the resilient gripping of the fabric edge portion within the groove. Such retainers are well known, and further description thereof is believed unnecessary.

The overall panel assembly and associated fabric retention structure as described above is already known, and in fact is illustrated by U.S. Pat. No. 5,238,515 as owned by the Assignee hereof.

To provide improved gripping engagement of the flexible fabric 19 within the gripping channel 24, the present invention initially involves applying a coating of a material with a high coefficient of friction, such as an adhesive material, to at least part of the inner surface of the fabric gripping channel 24 so as to create a tacky and tenacious but dry gripping surface which, when the fabric is inserted into and retained within the gripping channel, provides significantly improved gripping and hence holding capability with respect to the fabric, particularly thin and slippery fabrics, so as to prevent accidental loosening or dislodgement of the fabric.

The improved gripping associated with the fabric gripping channels is achieved in a preferred embodiment of the invention by initially applying a bead 31 (FIG. 5) of liquid or viscid coating material inside the gripping channel, preferably along the entire length thereof. The bead 31 of coating material is, as illustrated in FIG. 5, preferably applied to the inside surface of the outer channel wall 27 in the vicinity of the upper edge thereof, that is, close to but normally just below the curved upper corner 29. This liquid bead 31 as applied to the outer wall 27 is applied lengthwise along the entire channel part 22, preferably by effecting lengthwise movement of the frame rail 13 relative to an applicator or dispenser 32 which acts as a nozzle so as to apply the bead 31 to the wall 27 as the frame rail moves lengthwise relative to the dispenser.

In the illustrated and preferred embodiment, a pair of substantially identical applicators 32 are provided in side-by-side relationship, such as by being mounted on a common stationary support or frame 33, whereby each applicator 32 hence cooperates with one of the channel parts 22 so as to create formation of the bead 31 of coating material on the respective outer channel wall 27. The liquid coating material has properties, such as a cohesive and sticky fluid consistency, which enable it to adhere to the channel wall 27 so that the flow of the material can be controlled.

After the beads 31 have been applied to the outer walls 27 of the channel parts 22, the rail 13 is then relatively moved lengthwise with respect to a pair of air spray nozzles 34 (FIG. 6) which are positioned downstream of the applicator nozzles 32 and disposed for cooperation with the pair of channel parts 22. Each air spray nozzle 34 is disposed so that the discharge therefrom is positioned close to but oriented generally downwardly toward the bead and generally downwardly along the inner surface of the outer wall 27, with the nozzle also preferably having a slight angular orientation toward the inner surface of the wall 27. The air stream discharged from the nozzle 34, as the frame rail moves longitudinally relative to the nozzle 34, causes the bead 31 of coating material to be spread out both sidewardly and downwardly so as to effect a fairly uniform thickness of the coating material to be spread out over the inner surface of the outer wall 27. Depending upon the quantity of material applied at the bead 31, the material may be sufficient to effect coating of substantially the entire vertical extent of the outer wall 27, and in fact some of the coating material may flow downwardly and partially coat the upper surface of the base wall 28, whereby a thin coating 36 is hence formed over at least a significant portion of the inner surface area of the outer channel wall 27 substantially as illustrated by FIG. 6. The air nozzles hence are effective for not only spreading out the coating material to create a thin coating layer, but also are effective with respect to accelerating the drying (i.e. solidification) of the coating material so that a thin layer of coating material is hence applied to the inner surface of the outer leg of the channel part-so that the latter coated inner surface hence has a dry but high-friction surface, preferably a surface which may appear to be somewhat “tacky” or sticky to the touch, whereby the surface hence is highly effective with respect to creating a secure gripping engagement with the fabric which is subsequently inserted into the gripping channel 24. The air discharged from nozzles 34 may be heated to accelerate drying of the coating. The solidified coating hence has a tacky-dry characteristic.

As illustrated by FIG. 7, when the folded fabric edge portion 41 is inserted into the gripping channel 24, and the deformable retainer 42 is inserted into the channel 24 between the folded fabric layers, the deformed retainer 24 exerts sideward pressure toward the opposed channel legs 26 and 27 so that the folded fabric layers are hence gripped between the channel legs and the deformed retainer 42, with the fabric which engages the outer channel leg 27 being compressed against the tacky coating layer 36 which creates a highly effective gripping engagement similar to a releasable adhesive securement so as to resist pullout of the fabric from the gripping channel. The application of the coating layer to the outer wall 27 is particularly desirable since pullout of the fabric from the gripping channel, due to the wrapping of the fabric around the upper curved corner 29, hence must occur generally upwardly along the surface 27, and hence the high friction and tacky surface provided by the coating layer 36 is highly effective with respect to preventing movement of the fabric relative to the channel part 22, whereby the fabric sheet 19 hence retains its desired taut position as it extends across the face 18 of the side panel 17.

Referring to FIG. 4, there is diagrammatically illustrated a preferred arrangement for applying the coating to the channel parts 22 of the frame rail, prior to its assembly into the panel. The panel frame rail 13, 14 according to a preferred embodiment, is preferably roll formed from flat sheet metal such as sheet steel, with the flat sheet steel being fed into and through a conventional multi-stage roll forming arrangement 38 which, during passage of the sheet steel therethrough, causes the flat sheet steel to be progressively deformed so that a continuous elongate rail 13, 14 having the desired cross-sectional profile, such as illustrated by FIG. 3, is discharged from the end of the rail former, the latter being diagrammatically depicted in FIG. 4. The formed rail structure departing from the roll former 38 is elongate and continuous, and is subsequently subjected to further processing operations such as punching and piercing operations, as well as a severing or cutting operation which cuts the continuous formed rail into predetermined desired lengths. Prior to cutting of the roll-formed rail into desired lengths, however, the channel parts of the rail are preferably subjected to the coating process.

More specifically, the continuous moving formed rail 13, 14 after departing the roll former 38 passes through a coating application station wherein the pair of applicators 32 are disposed in sidewardly spaced relation and positioned above the moving rail, generally as illustrated in FIG. 5, so as to apply a bead of coating material into each of the channel parts 22 as the continuous formed rail is moved downstream away from the roll former 38 in the direction indicated by the arrow 43.

After the moving continuous formed rail passes beneath the applicators 32, then shortly thereafter the moving rail having the adhesive beads 31 associated with the channel parts 22, moves into and through a spreading or distributing station defined by the pair of air nozzles 34 which are disposed over the sidewardly spaced channel parts so as to direct streams of air (such as ambient temperature air) downwardly against the beads, substantially as illustrated in FIG. 6. When the moving rail passes under the nozzles 34, the tips of the nozzles 34 are positioned closely adjacent and generally directly above the beads 31 and discharge air streams directly downwardly onto the beads 31, and hence downwardly into the grooves, causing the beads to flow downwardly and thin out so as to create a relatively uniform thin coating over the inside surface of the outer walls of the channel parts. The discharged air stream, in addition to distributing the material of the bead, also accelerates the drying of the material as it thins out over the inner surface of the channel wall. The continuous rail structure, after passing under the air nozzles 34, continues moving in a downstream direction (rightwardly in FIG. 4), and the inside surface of the channel parts 22 are now at least partially coated with a thin layer of the coating material, preferably on the inside surface of the outer wall of the channel part as described above. The continuous moving rail can thereafter be subjected to subsequent forming operations such as punching or piercing operations, and is also subjected to a severing or cutting operation which cuts the continuous rail into individual edge rails 13, 14 of predefined length. The predefined length edge rails can thereafter be subsequently treated and shaped as necessary, and individually stored and handled, and thereafter assembled to define the ring-shaped frame 12 of a panel. When so assembled, one or each side face of the panel is then covered with a sheet 19 of fabric, and the edge portions of the fabric sheet are folded over and inserted into the channel parts 22 which extend along the four side edges of the panel member, and appropriate deformable elongate retainer strips or splines 42 are then inserted into and along each of the channel parts in the manner illustrated by FIG. 7 so as to effect secure but removable retention of the fabric edge within the channel part 22, thereby maintaining the fabric 19 in a stretched or taut condition as it extends across the side face of the panel 11.

The insertion of the folded fabric edge into the channel part 22 of the edge rail, and the insertion of the elongate deformable retainer 42 into the rail channel part between the folded edge portion of the fabric, generally occurs substantially simultaneously, and typically utilizes a thin but elongate inserting blade or tool so that, with the fabric edge portion and retaining element positioned to overlap the mouth of the channel, the inserting tool can then be engaged and pushed inwardly so that the fabric edge portion and retainer strip are inserted downwardly into the bottom of the retaining groove while at the same time effecting stretching of the fabric across the face of the panel. The technique associated with these assembly steps is well known.

According to the process of this invention, the rails 13, 14 of a panel frame 12 are preferably provided with a thin layer of coating material extending along the inside surface of each channel part 22 throughout the length of each rail. The coating material is preferably applied as a wet bead which is then fanned out or distributed so as to define a thin layer over a wider transverse surface area which extends lengthwise throughout the length of the rail channel part. This coating material is allowed to fully dry prior to panel assembly, and defines an inner surface on the channel part which has a sticky or tacky characteristic so as to provide a high friction when contacted with the fabric. The coating can be applied while the rail is being roll formed as a continuous formed member prior to severing of individual rail lengths, or can be applied to the rail members after they are of the desired formed length, particularly if the rail members are formed by some other technique such as stamping or the like. The rail members defining the panel frame, which rail members may have different cross-sectional shapes depending upon whether they function as top, bottom or side rails, are then assembled to define the rectangular frame of the panel, such as by welding or otherwise securing the individual edge rails at the meeting corners of the frame. After the core and side panels of the panel assembly have been assembled to the frame, then the fabric sheet is positioned to overlie each side face. The fabric sheet is initially oversized so that a portion of the sheet adjacent each edge thereof will overlie the respective edge rail and provide a sufficient edge portion of fabric so as to permit it to be folded over and inserted into the respective adjacent edge channel 22. The folded edge portion of the fabric and the elongate deformable retaining element are inserted into the respective edge channel by a suitable tool, such as a blade (which may be formed as a roller) so as to assemble the edge of the fabric and the retainer into the gripping channel substantially as illustrated by FIG. 7. When this has been accomplished along all four edges of the panel assembly, the resulting fabric is maintained in a stretched or taut condition so that it extends over the exposed side face of the panel, and all four side edges of the fabric sheet are appropriately secured and positively retained within the respective edge channels 22. The providing of the tacky coating material on the outer leg of the channel part provides a surface with a high coefficient of friction for positive gripping engagement with the fabric since this area of engagement effectively extends parallel with the primary (i.e. exposed part) fabric sheet which extends across the outer side face of the panel, with the intermediate edge portion of the fabric sheet being wrapped around through generally a 180° bend, whereby any force tending to withdraw the fabric edge portion from the channel 22 has to act generally directly along the high friction tacky surface defined by the coating material, and hence a very secure gripping engagement with the fabric sheet is achieved.

At the same time, however, even though the coating material has a sticky or tacky surface, it nevertheless maintains its integrity in that it does not permanently adhere to the fabric so that the fabric can subsequently be removed, if desired, for example due to the fabric becoming damaged or worn. When removal of the fabric is desired, then an appropriate tool is inserted into the channel part so as to engage and effect removal of the deformed retaining element 42. After removal of the elongate retainer 42, the folded fabric edge can then be readily withdrawn from the gripping channel, thereby enabling the entire fabric sheet to be removed from the panel and a new fabric sheet remounted.

The coating material, however, due to its sticky or tacky surface, is believed to create a releasable (i.e., weak) adhesive engagement with the fabric sheet due to the latter being pressed against the coating surface by the compressed retainer.

The coating material as applied to the channel part of the edge rail is, according to a preferred variation of the invention, a water-based pressure sensitive type of adhesive which will readily adhere to the metal surface of the edge rail, and which when dry or solidified, provides an exposed surface having a sticky or tacky characteristic for providing desirable gripping engagement, such as with the fabric which is pressed thereagainst. At the same time, however, the coating material has good bond strength with respect to its engagement with the metal of the edge rail, and if properly dried prior to engagement with the fabric, does not bond or adhere to the fabric.

An adhesive which has been determined to be particularly desirable for this application is the Fastbond brand of pressure-sensitive adhesives manufactured by 3M, and specifically the 4224-NF pressure-sensitive adhesive. This adhesive material, when applied to the channel part as an elongate bead extending lengthwise therealong, remains basically intact and adhered to the wall of the channel part since the material when in its liquid condition does not exhibit any significant running.

When the adhesive bead is subjected to the air blast discharged from the nozzles 34, this air blast is sufficient to fan or spread out the material so that it more uniformly covers the wall of the channel over a significant transverse extent, as well as lengthwise along the channel, and also accelerates the drying of the material by evaporating or driving off the solvents or volatile constituents, thereby creating a thin solidified coating which provides a greater gripping surface area while at the same time minimizing the quantity of adhesive utilized.

The air blasts discharged from the nozzles 34 can be heated air (in place of the ambient temperature air) which, in addition to fanning out the bead of adhesive, accelerates the drying thereof so that the dried or solidified adhesive hence creates a layer which is effectively bonded to the inner surface of the channel part. When so bonded, the edge rails can hence be subsequently handled as well as stored for significant periods of time prior to their being assembled into a panel assembly.

While the bead of adhesive material defining the coating is preferably applied to the inner surface of the outer channel wall as described above, other application locations for the material are possible. For example, as an alternative the adhesive bead can be deposited along the bottom of the gripping channel 22, whereupon the air blast would then be directed downwardly into the channel so as to effect fanning or spreading out of the material upwardly along generally both sides of the channel part. With this latter arrangement, however, there is less control over the spreading out of the adhesive material in terms of its location relative to the inner surface of the channel part, and additional splattering of material outside the channel is likely, so that additional confinement of the spraying and spreading operation is believed necessary.

The pressure sensitive adhesive, in a preferred embodiment, is a viscoelastic material which in solvent-free form (i.e. solidified form) remains permanently tacky.

Although a particular preferred embodiment of the invention has been disclosed in detail for illustrative purposes, it will be recognized that variations or modifications of the disclosed apparatus, including the rearrangement of parts, lie within the scope of the present invention.

Claims

1. A method of forming a panel structure having a flexible covering sheet secured thereto and extending exteriorly over one large side face thereof, comprising the steps of:

providing a set of elongate metal frame members each having a channel part extending longitudinally thereof and defining therein a longitudinally-extending groove having a mouth which opens sidewardly of the respective frame member, the channel-like part having an inner generally U-shaped wall surface which defines said groove;

adhering a thin layer of a pressure-sensitive type adhesive to an inner wall surface of said groove along the length thereof with said layer extending transverse of said groove over at least a portion of the transverse dimension of said inner surface, said layer defining thereon a tacky high-friction exposed surface;

securing the set of frame members together to define a generally rigid rectangular frame;

positioning a core structure across the open interior of the rectangular frame;

providing a large flexible covering sheet of a size somewhat greater than the size of the side face of the frame;

positioning the flexible covering sheet so that it extends across the side face of the frame and core structure but is free of fixed securement therewith, with edge portions of the covering sheet extending over the mouths of the grooves;

inserting the edge portions of the covering sheet into the respective grooves so that the edge portion of the covering sheet directly overlies the exposed surface of the coating layer; and

inserting an elongate but transversely deformable retaining element into the groove so that the deforming element is compressed between opposite sides of the groove and clampingly presses the edge portion of the fabric sheet against the coating layer to effect a secure gripping engagement therebetween.

2. A process according to claim 1, wherein the coating material applied to the inside surface of the groove is applied to the outer leg of the channel part.

3. A process according to claim 1, including the steps of applying a bead of the adhesive in liquid form to the inner surface of the channel part with the bead extending generally throughout the length of the groove, and then subjecting the bead to a stream of air discharged from a nozzle to effect fanning out of the adhesive to define a thin layer of greater width which coats the inner surface of the groove in the lengthwise direction thereof.

4. A process according to claim 3, including the step of discharging the air toward the interior of the groove and generally transversely relative to the bead to effect fanning out of the adhesive material and rapid drying thereof as the material is spread out into a thin layer.

5. A process according to claim 4, including the step of heating the discharged air.

6. A process according to claim 4, wherein the channel part defines generally opposed inner and outer legs which define the groove therebetween, and wherein the bead is applied to the outer leg in close proximity to the open mouth of the groove.

7. A process according to claim 6, wherein the pressure-sensitive material is a water-based high-viscosity pressure-sensitive adhesive.

8. A process according to claim 1, including the steps of initially roll-forming a thin flat sheet of steel so as to define an elongate profile having the cross section of the metal frame member, forming the coating in the channel part of the profile after the profile is discharged from a roll former; and

thereafter cutting the profile into desired lengths corresponding to the metal frame member.

9. A panel structure constructed in accordance with the process of claim 1.

10. A process for forming an upright wall panel assembly having a surrounding rigid frame defined by elongate metal edge rails extending lengthwise along the upper, lower and vertical edges thereof, each edge rail having a pair of generally parallel channel parts extending lengthwise thereof and defining retaining grooves which extend lengthwise of the respective edge rail and open sidewardly, and a pair of large flexible fabric sheets positioned to overlie opposite side faces of the panel member, each flexible fabric sheet having edge portions which respectively overlie and are retained within the respectively adjacent retaining grooves defined in the edge rails, comprising the steps of:

applying an elongate strip or bead of coating material onto an inner wall surface defining each said groove;

spreading the strip of material so that it defines a wide but thin layer which overlies at least a part of the inner wall surface of the groove and extends lengthwise thereof;

drying the thin layer of coating material so that it adheres to the wall of the groove and defines an exposed high-friction surface; and

thereafter inserting an edge portion of the fabric together with an elongated but transversely deformable retainer into the groove so that the retainer is transversely deformed between opposite sides of the groove and the retainer clampingly presses the edge portion of the fabric against the exposed high friction surface of the coating layer.

11. A process according to claim 10, wherein the coating layer is applied to the outer side of the groove.

12. A process according to claim 10, wherein the coating layer is applied to the edge rail and dried prior to the edge rail being assembled to the frame of the panel assembly.

13. A process according to claim 10, wherein the coating material comprises a water-based pressure-sensitive adhesive, and wherein the coating material is initially applied interiorly of the groove as a small bead which extends lengthwise along the channel throughout substantially the entire length thereof, and the bead thereafter being transversely spread out to define the thin layer.

14. The process according to claim 10, including subjecting the bead to a transversely oriented jet of discharged air for effecting transverse spreading out of the adhesive material.

15. A process according to claim 14, wherein the discharged jet of air is heated to assist in drying of the material as it is spread out to define said thin layer.