EP1157177A1

EP1157177A1 - Drywall corner finishing device

Info

Publication number: EP1157177A1
Application number: EP99905759A
Authority: EP
Inventors: Paul E. Stibolt
Original assignee: Individual
Current assignee: OMNIFLX PROFILES Inc
Priority date: 1999-02-05
Filing date: 1999-02-05
Publication date: 2001-11-28
Anticipated expiration: 2019-02-05
Also published as: CA2362050A1; AU2584899A; DE69932742D1; DE69932742T2; AU756191B2; EP1157177B1; HK1044033B; EP1157177B8; HK1044033A1; EP1157177A4; CA2362050C

Abstract

A finishing device used to form a corner between two panels of drywall has a flexible joint (100) along a predetermined axis. Two wings (102, 104) are connected to and extend outwardly in a diverging relation from the flexible joint (100) to form a corner having an adjustable angle. Each wing (102, 104) has a front surface (106), a rear surface (108), and an edge distal (204) from the flexible joint (100). This edge (204) abuts one of said drywall panels and has a thickness of the drywall panel. Alternatively, the edge (204) has an adjustable thickness to fit various thicknesses of drywall panel. A layer of primer or adhesive laminate is applied to the front surface of the wings so that paint can bond to the front surface. The finishing device is capable of forming both inside and outside corners. To form inside corners, the finishing device bends along the flexible joint (100). To form outside corners, strips parallel to the flexible joint (100) are removed from the rear surface of the wings (102, 104) and the finishing device is folded along the openings thus created.

Description

DRYWALL CORNER FINISHING DEVICE

Related Application

This application is a continuation- in-part of the applicant's co- pending U.S. Patent Appln. Ser. No. 08/513,716 filed on August 11, 1995, entitled "Drywall Comer Fimshing Device," which is a continuation- in-part of applicant's U.S. Patent Appln. Ser. No. 08/234,423 filed on April 28, 1994, which issued as Patent No. 5,459,969 on October 24, 1995, entitled "Drywall Corner Fimshing Device."

Background of the Invention 1. Field of the Invention. This invention relates to fimshing interior walls. In particular, this invention relates to f ishing the edges at intersections where two walls meet.

2. Statement of the Problem. Drywall panels are widely used in the construction industry for foiming the interior walls and ceilings of rooms. Drywall panels are made of a gypsum or reinforced gypsum core covered with paper. Drywall panels have the advantages of being easy to cut to desired sizes and to attach to assorted types of framing. However, it is very difficult to cut^< drywall panels so that the edges are perfectly straight and smooth and can meet to form a perfectly straight comer, which is aesthetically to be desired. In addition, when the drywall panels are cut to the desired sizes, the edges of the panels are left exposed. This exposed gypsum core is soft and tends to crumble unless the severed edges are somehow protected. This is especially important at outside wall comers. When walls and ceilings are built of fran ing materials such as wood, the inside and outside comers thereby formed are seldom perfectly straight. Small variations in the sizes of the wood fraining members, warping of the wood, and inconsistent building practices lead to imperfectly straight comers where walls and ceilings meet, and where walls end at doorways and passageways. When drywall panels are then attached to the crooked framing materials, their intersections will also be crooked.

An assortment of devices have been used to provide a smooth and durable finish for the intersections where two pieces of drywall abut to form an inside or outside comer. Among the conventional devices used are drywall tape and metal comer beads. Conventional drywall tape is provided in narrow, elongated ribbons or strips of porous paper wound into rolls. The paper is sometimes perforated to increase moisture penetration and to prevent air bubbles from being entrapped behind the tape. The drywall tape is first applied to joints and edges of abutting drywall panels and is then covered with wet plaster, sometimes called "mud." The plaster is feathered and smoothed along the edges of the tape to conceal the demarcations between the tape edges and the drywall panels to which the tape is applied. When the wet plaster has dried, the tape and drywall can be painted or otherwise covered with a suitable wall covering. A great deal of skill is needed to apply the plaster to both sides of an inside corner such that a perfectly straight intersection is achieved. Also, to correct the crookedness resulting from the warped framing members and' inconsistent building practices described above, often several coats of plaster must be applied, with an entire day of drying time needed between each coat. Even then, a perfectly straight comer seldom results. It is also likely that, unless in the most highly skilled hands, the plaster trowel will mar the first side of the plaster while the second side is being applied. Once the plaster has been applied and dried, it must be sanded to an appropriate finish to provide a surface suitable for the application of paint or wallpaper.

Coffered and vaulted ceilings have recently become very popular among home builders and buyers. Often the peak of such ceilings will form an acute angle. It is difficult to fit a conventional plaster trowel into such angles. Because drywall tape is formed of paper, it is quite flexible and will conform to various surface configurations of the edges of intersecting panels of drywall. When conventional drywall tape is used at the outside comers of walls, the flexibility of the tape often results in a comer demarcation that is irregular, since the tape conforms to irregularities in the exposed, severed edges of the drywall panels. The tape is also fragile and does not stand up well to the constant physical abuse suffered by outside corners. As a consequence, conventional drywall tape cannot be used at exposed outside comers.

To finish outside comers in building construction, therefore, metal comer beads are often used. Conventional metal beads are configured in an L- shaped or angle-shaped cross section and are typically fabricated from elongated perforated strips of metal, such as galvanized steel, permanently deformed with a lengthwise 90-degree bend to form elongated angles. The metal beading is typically positioned at the intersections of adjacent drywall panels that meet at right angles to form an outside comer within a room. The sections of metal beading are nailed in place through the drywall panels to wooden supporting structural members located behind the drywall panels. Wet plaster is then smoothed into place to cover the metal flanges or leg members' of the metal beading, and the edges of the plaster are smoothed and feathered to attempt to conceal the metal edges.

While the rigidity of the metal beading does allow an outside comer of an inside building wall to be finished with a sharp, straight edge, which is aesthetically pleasing, the use of metal beading involves some significant problems. Over time, the metal comer bead will rust, thereby producing rust stains that are clearly visible on the surfaces of the walls at the comer. It is not always possible to completely cover the edges of the metal flanges or the nail heads used to attach the metal comer bead to the drywall panel, detracting from the desired smooth appearance of the wall. Cracks often develop in the overlying plaster at the outer edges of the flanges. To prevent this from happening, often two or three coats of plaster are applied, with prior coats allowed to dry and harden, which may take as long as 24 hours, before a subsequent coat is applied. When the comers are crooked or jagged due to problems with the underlying framing, metal beads do not cover enough surface area or have enough flexibility to correct the inequalities that exist. Another problem is inherent in the fact that the malleable metal from which the metal beads are made has a very poor memory and is subject to being dented or wrinkled, after which it is difficult to straighten it to produce a smooth finish. Because of the rough, handling to which most of the material at a work site is subjected, it is not uncommon for the strips to be wrinkled, dented, and perhaps twisted, thus rendering them either unusable, or usable only to produce an inferior end result. In addition, the metal strips are used in large quantities in construction and can add up to considerable cost. A number of comer finishing devices have been developed to address the above-described problems. .Among these devices are the following:

Inventor U.S. Patent No. Date issued Swanson 3,444,657 May 20, 1969

Baker 3,989,397 Nov. 2, 1976

Ellingson 4,012,878 Mar. 22, 1977

Lamb 4,313,991 Feb. 2, 1982 Schaafsma 4,315,390 Feb. 16, 1982

Weinar 4,553,363 Nov. 19, 1985

Schneller 4,624,087 Nov. 25, 1986

Bernard 4,719,732 Jan. 19, 1988

Tucker 4,863,774 Sept. 5, 1989 Conboy 5,037,686 Aug. 6, 1991

Tucker 5,045,374 Sept. 3, 1991

Weldy 5,086,598 Feb. 11, 1992

Ritchie et al. 5,131,198 July 21, 1992

Rutkowski et al. 3,964,220 June 22, 1976 Cannon 1,215,345 Dec. 9, 1970

Swanson and Lamb describe plastic joint strips that can be reversibly bent to be adhesively secured to both inside and outside comers.

Baker shows an outside comer connector for waterbed pedestals in which the panels forming the pedestal are inserted into the connector.

Ellingson provides a double-layer wall member guard structure for outside comers made of a resilient material.

Schaafsma describes two types of wallboard comers, one for inside comers that is held in place by putty and another for outside comers that is held in place by the drywall panels themselves. The former is disadvantaged by the fact that it is held on only by putty; if the putty does not adhere well to the drvwall. the comer will become loose. The outside comer must be placed' under the drywall panels, involving considerable bending or. if placed on the comer before the panels, a certain amount of extra effort to hold the comer in place while the panels are being nailed over it. Both comers use tape to provide a smooth top finish that can be blended in with the drywall finish by applying plaster and sanding. Weinar provides a plastic or metal T-shaped comer construction in which the post of the T sits between two abutting pieces of drywall and the cross bar lies atop the drywall panels. Part of the paper covering from one panel is wrapped around the cross bar to provide a finished appearance, leaving a ridge down one side of the comer. This comer construction can only be used on outside comers.

Schneller describes yet another type of metal outside comer bead in which an additional flange extends over the edge of the drywall board forming the outside comer. Ridges are left on both sides of the comer, and this comer bead can only be used on outside corners. Bernard presents a plastic L-shaped outside comer cover that uses heat- shrinkable plastic tape along the arms both as a method of attachment and as a method of providing a smooth junction between the cover and the drywall. This cover can be used for outside comers having a variety of angles.

Tucker provides a paper drywall ribbon having a centrally located plastic bead extending longi dinally along the ribbon. Plaster is used to attach the ribbon to the drvwall. This plastic bead is designed to be used with outside comers only.

Conboy describes a plastic drywall tape that can be used on both inside and outside comers. Again, this plastic tape is held on the comer with plaster, and plaster is used to provide a finished appearance.

Tucker describes a stiff plastic strip with a curved center section and two flanges that is attached to outside or inside comers with adhesive. The flanges are then covered with paper tape strips and plaster. Weldy provides a wall edging system for both inside and outside comers that comprises a plastic strip having an arcuate center portion to which are attached two flanges at right angles. The strip is attached to the drywall with nails. Plaster is then smoothed over the strip to finish the edges. The side of the strip facing out toward the room can be finished with primer.

Ritchie et al. describe a comer bead for outside comers that has a metal core and that is completely covered by paper. This bead has a rounded nose and side flanges. The paper covering is further coated with a reinforcing emulsion. The comer bead is nailed to the drywall, and plaster is used to hide the edges.

Rutkowski et al. describe an elongate strip to be placed between the junctions of adjacent drywall boards forming a planar wall in order to absorb movement within the wall. The strip has two flanges attached on either side of a central flexible portion. Cannon describes a building in which the walls are inserted into comer posts. The posts have two channels into which are place the edges of walls. The walls are held within the channels by a bolt and comer plate that connects with cladding on the walls.

A need exists for a drvwall comer finishing device that can be used on both outside and inside comers having various angles and that provides a primed surface for either orientation. A further need exists for a drywall comer finishing device that can be used to cover juxtaposed outside comers, such as are found at the edges of interior doorways or other openings of various dimensions, for example, passthroughs from one room to another. Because of the crooked comers that result from warped building materials and inconsistent building practices, a need exists for a comer finishing device that will provide a perfectly straight comer without the use of multiple coats of plaster. A finishing device is also needed that will simplify installation of drywall in acutely angled inside comers and minintize the need to use plaster.

Another consideration is the fact that drywall panels are made in a variety of thicknesses. For example, drywall panels may be % inch wide, Vz inch wide, % inch wide, or other widths. There is a need for a drywall comer finishing device that can be used for all thicknesses of drywall panel.

None of the above-described drywall comers fulfills these needs.

3. Solution to the Problem. The drywall comer finishing device described herein can be used for both inside and outside comers having various angles. Builders will not have to order two or more versions to cover different types of comers. The drywall comer f ishing device described herein can also be used to cover two adjacent outside corners without requiring the use of a ' narrow strip of drywall panel between the comers and two finishing devices, one for each outside comer. A layer of primer or laminate covers the side of the drywall comer finishing device of the present invention that faces into the room. Because of this primer or laminate layer, plaster need only be used on the outside edges of the comer fimshing device where it abuts the drywall. The drywall comer fmishing device described herein has a width generally equal to that of the drywall panels, so that little plaster is needed to fill in the area where the drywall panels meet the finishing device. The drywall comer finishing device of the present invention is capable of biding crooked, uneven comers no matter how irregular the deviations may be. The present drvwall comer finishing device is nailed directly to the framing members of the wall, thereby providing stability. Finally, the drywall co er finishing device is adjustable to fit various thicknesses of drywall panels. Summary of the Invention

A finishing device used to form a comer between two panels of drywall has a flexible joint extending along a predetermined axis. Two wings are connected to and extend outwardly in a diverging relation from the flexible joint to form a comer having an adjustable angle. Each wing has a front surface, a rear surface, and an edge distal from the flexible joint. This edge abuts one of the drywall panels and has a thickness approximately equal to the thickness of the drywall panel. In an alternative embodiment, the thickness of the distal edge can be varied so that the finishing device fits drywall panels of different thicknesses. A layer of primer or adhesive laminate is applied to the front surface of the wings so that paint or wallpaper or other wallcoverings can bond to the front surface. The fimshing device is capable of forming both inside and outside comers. To form inside corners, the finishing device bends along the flexible joint To form outside comers, strips parallel to the flexible joint are removed from the rear surface of the wings and the finishing device is folded along the openings thus created.

Brief Description of the Drawings

The present invention can be more readily understood in conjunction with the accompanying drawings, in which:

FIG. 1 is a partial perspective view of the drywall comer fimshing device in accordance with the present invention; FIG. 2 shows a cross-sectional view of the drywall comer fmishing device in accordance with the present invention;

FIG. 3 is a detailed cross-sectional view taken from the outlined section of FIG. 2 showing the front surface of the drywall comer finishing device in accordance with the present invention covered with a layer of primer; FIG. 4 shows a detailed cross-sectional view taken from the outlined section of FIG. 2 showing the front surface of a second embodiment of the drywall corner fmishing device in accordance with the present invention covered with a layer of adhesive laminate;

FIG. 5 shows a cross-sectional view of the drywall comer finishing device in accordance with the present invention bent to fit inside comers;

FIG. 6 is a detailed cross-sectional view of the center joint of the drywall comer finishing device as shown in FIG. 2;

FIG. 7 shows a detailed cross-sectional view of the center joint of the drywall comer finishing device as shown in FIG. 5; FIG. 8 shows a cross-sectional view of the drywall comer finishing device in accordance with the present invention applied to an inside comer between a wall and a ceiling;

FIG. 9 is a cross-sectional view of the drywall comer finishing device in accordance with the present invention applied to an inside co er formed at' the top of a ceiling: FIG. 10 shows a cross-sectional view of the drywall comer finishing device in accordance with the present invention applied around two outside comers;

FIG. 11 is a cross-sectional view of the drywall comer finishing device in accordance with the present invention applied around two outside comers separated by a greater distance than the outside comers shown in FIG. 10;

FIG. 12(a) shows a detailed cross-sectional view of the removable strip of the drywall comer finishing device in accordance with the present invention; FIG. 12(b) is a detailed cross-sectional view showing the removal of the removable strip of FIG. 12(a);

FIG. 12(c) is a detailed cross-sectional view showing how the drywall comer finishing device is folded after the removal of the removable strip of ^• FIG. 12(a); and FIG. 13 is a cross-sectional view of the drywall comer finishing device in accordance with the present invention showing the application of plaster to the joint.

FIG. 14 is a cross-sectional view of an alternative embodiment of the drywall corner finishing device. FIG. 15 is a perspective view of another embodiment of the drywall comer fimshing device.

FIG. 16 is a perspective view from another angle of the drywall comer finishing device of FIG. 15.

FIG. 17 is a perspective view of yet another embodiment of the drywall corner finishing device.

FIG. 18 is a perspective view from another angle of the drywall comer finishing device of FIG. 17. FIG. 19 is a perspective view of an additional embodiment of the drywall comer fjnishing device.

FIG. 20 is a perspective view from a different angle of the drywall comer finishing device of FIG. 19. FIG. 21 is a perspective view of a further embodiment of the drywall comer finishing device.

FIG. 22 is a perspective view from another angle of the drywall comer finishing device of FIG. 21.

FIG. 23 is a perspective view of another embodiment of the drywall corner f shing device.

FIG. 24 is a cross section of the drywall comer finishing device of FIG. 23.

FIGS. 25(a) and 25(b) are partial cross sections of the drywall comer finishing device of FIG. 23 illustrating the expansion of the device.

Detailed Description

Turning to FIG. 1, the left 102 and right 104 wings of the drywall comer finishing strip are attached to a flexible center joint 100 and extend outwardly therefrom to a distal edge 110. The wings 102, 104 have a front surface 106 and a rear surface 108. The front surface 106 and rear surface 108 extend outwardly beyond the distal edge 110 of the wings 102, 104 to cover the distal edge 110. When the drywall comer firiishing device covers either an inside comer or an outside comer, the rear surface 108 of the device is juxtaposed to the framing of an interior wall while the front surface 106 faces out into the room, contiguous with the surface of the drywall panels forming the wall. The front surface 106 may be covered with a layer of primer 300 as shown in FIG. 3 so that any paint or wallcovering that is eventually used to decorate the wall will adhere easily. Alternatively, the front surface 106 may have an adhesive laminate 400 attached to it as shown in FIG. 4.

The structure of the drywall comer finishing device is more clearly seen in FIG. 2. The flexible center joint 100 is preferably arcuate, but it is to be expressly understood that any joint shape, such as V-shaped, U-shaped, C- shaped, etc., can be used that allows the device to bend through a variety of angles at the center joint 100. The center joint 100 extends along an axis that extends linearly to form a comer or edge. A number of struts 206 separate the rear surface 108 of each wing 102,

104 from the front surface 106 of each wing 102, 104. In the preferred embodiment shown in Figs. 1 and 2. the pattern of struts 206 provides stability to the structure of the comer device and also allows the device to be folded ^< around outside comers, as discussed in more detail below. It will be obvious to one skilled in the art that the pattern of struts 206 shown in Figs. 1 and 2 is not the only pattern that will provide these features of stability and folding and that other patterns would be suitable and are to be included in the present invention. The edge 202 of the rear surface 108 extends beyond the edge 200 of the front surface 106. The distal portion 204 of the front surface 106 tapers slightly toward the rear surface 108 so that, as discussed in more detail below, the edge of a drywall panel can be placed in the space 114 between the front surface 106 and the rear surface 108 such that the edge 202 of the rear surface 108 and the edge 200 of the front surface 200 are in close apposition to the drywall panel. The rear surface 108 contains a number of removable strips 208, 210 that are removed when it is desired to fold the drywall comer fimshing device around outside comers, as discussed in more detail below.

FIG. 8 illustrates the inside comer formed when a vertical wall meets a coffered or cathedral ceiling. FIG. 9 shows the inside comer formed at the vault of such a ceiling. Depending on the design of the building, these comers may have angles ranging from less than 90 degrees to 180 degrees. When the drywall comer finishing device is used to finish an inside comer, the rear surface 108 is first placed directly against the framing. The center joint 100 flexes from 180 degrees, shown in FIG. 6, to the appropriate angle needed to fit the angle made by the comer, as shown by arrow 500 in FIG. 5 and arrow 700 in FIG. 7.

As an example, in FIG. 8, the finishing device is attached to the wall framing 800 and ceiling rafter 802 by use of nails 806. The finishing device is made of plastic soft enough to permit the nails 806 to be driven through the flange 112 of the rear surface 108 without the need for pre-formed holes. It is to be expressly understood that other methods such as the use of screws, bolts. ' adhesive, etc.. will be equally efficacious in attaching the fmishing device to the supporting members of the wall or ceiling. The attachment location of the device and the positions of the nails 806 can be varied to enable the device to correct inequalities that may exist within the framing and from one framing member 800 to the next. If necessary, shims may be placed behind the device before it is attached by nails 806. After the device has been securely attached to the framing 800 and rafter 802, the edges of the drywall panels 804 are inserted into the spaces 114 between the front surface 106 and rear surface 108, such that the edges of the drywall panels 804 abut the distal edges 110 of the wings 102, 104. It can be seen in FIG. 8 that the spaces 114 between the front surface 106 and rear surface 108 are just large enough to accommodate the drywall panels 804 and that the front surface 106 and rear surface 108 are closely juxtaposed to the drywall panels 804. The drywall panels 804 thus hide the nails 806. The drywall panels 804 are attached to the framing 800 and rafter 802 in the usual fashion. As FIG. 13 shows, plaster 1300 is then applied to the tapered distal portion 204 of the front surface 106 and the tapered edge of the drywall panel 804 to hide the edge 200 and provide a smooth, level surface. Because plaster 1300 is applied only to the tapered portion 204 of the finishing device, difficulties inherent in plastering within corners are avoided. Such difficulties include, among others, the difficulty in maneuvering a plaster trowel within a comer, the skill needed to produce a perfectly straight edge where the two sides of the comer meet, and the need for several layers of plaster 1300 to completely hide the joint between the finishing device and the drywall or to correct the inequalities resulting from mis-sized, mis-placed, or warped framing members, with each layer requiring considerable time to dry. Once plaster 1300 has been applied, the surface of the wall can be finished by painting, wallpapering, or any other method desired. The primer 300 bonded to ' the front surface 106 enables paint or other wallcoverings to adhere to the front surface 106 of the finishing device. In another embodiment, a laminate 400 can be adhesively affixed to the front surface 106 to provide a surface for subsequent painting.

A second example of the use of the finishing device for inside comers is shown in FIG. 9. Here, the fimshing device provides an inside comer essentially as described above, except here the comer is that formed by the vault of a coffered ceiling. The device is attached to the rafters 900 by driving nails 904 through the flanges 112. The attachment location of the device and the positions of the nails 904 can be varied to enable the device to correct inequalities that may exist within the rafters 900 and from one rafter 900 to the next. If necessary, shi s may be placed behind the device before it is attached by nails 904. The edges of the drywall panels 902 are then inserted into the spaces 114 between the front surface 106 and rear surface 108. As above, these spaces 114 are just large enough to accommodate the edges of the drywall panels 902, so that the front surface 106 and rear surface 108 are in close apposition to the drywall panels 902. The drywall panels 902 thus hide the nails 904. The drywall panels 902 are attached to the rafters 900 in the usual fashion. Plaster 1300 is then applied to the tapered distal portion 204 of the front surface 106 and the edge of drywall panels 902 to provide an even surface. Because of the primer 300 or laminate 400 covering the front surface

106, it is not necessary to use plaster on the remainder of the front surface 106, and the difficulties of plastering within the tight angles formed by inner comers are avoided. The surface of the wall is then painted or otherwise finished as desired. Often outside comers exist next to each other. Two examples of such outside comers are shown in Figs. 10 and 11. Figure 10 illustrates outside comers formed by 2-by-4 framing boards 1000. 1002. and FIG. 1 1 shows ' outside comers formed bv 2-bv-6 framing boards 1 100. 1 102. The rear surface 108 contains at least two sets of removable strips 208, 210. It is to be expressly understood that the removable strips 208, 210 can be located in any convenient place on the rear surface 108 and that the present invention is not limited to the locations of the strips 208, 210 shown. Strips 208 are removed when 2-by-4 boards 1000, 1002 are used, and strips 210 are removed when 2-by-6 boards

1100, 1102 are used. Once the strips 208 or 210 are removed, the front surface 106 can be bent around both outside comers. This process is described below and shown in Figs. 12(a) - 12(c).

A removable strip 208 is held by a number of thin tags 1200 between the struts 206 parallel to the rear surface 108. To remove a strip 208, one need only break the thin tags 1200. The strip 208 is then removed in the direction of the arrow 1202 and discarded. The front surface 106 is then bent in the direction of the arrow 1204 to form a comer that will fit around one of the adjacent outside comers. It is to be understood that a similar but mirror-image process occurs with the second strip 208, so that the front surface 106 can be bent to form a second corner that will fit around the second of the juxtaposed outside comers. The strips 210 are removed in the same manner to permit the finishing device to be bent around two outside comers that are further apart.

Once the strips 208 or 210 are removed and the front surface 106 is bent, the finishing device is attached to the framing board 1000 or 1102 by use of nails 1004 or 1104. The attachment location of the device and the positions of the nails 1004, 1104 can be varied to enable the device to correct inaccuracies that may result from warped or mis-sized framing boards 1000, 1002, 1100, 1102 or inconsistencies in building practices. If necessary, shims may be placed behind the device before it is attached by nails 1004, 1 104. The drywall panels 1006. 1 106 are inserted as described above for inside comers^, and the joint between the finishing device and the drywall panels 1006, 1106 is' finished in the same manner as described above and shown in FIG. 13 for inside comers.

FIG. 14 shows a cross-sectional view of an alternative embodiment of the present invention. This embodiment provides only one set of removable strips 210 located equidistant from the center joint 100. The number and complexity of the struts 206 has also been reduced to simplify manufacture of the device by plastic extrusion. The arrangement of the distal stmts 207 has also been changed for greater support to the tapered end 204 of the front surface of the device. If a portion of the rear flange 112 is drawn rearward to accommodate an uneven section in a rafter, the distal strut 207 will tend to allow the tapered front surface 204 of the device to maintain a straight edge in spite of irregularities in the underlying rafters. Assuming the device is molded from some type of flexible plastic, the end strut 205 will deform as necessary to accommodate such irregularities. Further examples of the present invention are illustrated in Figures 15 through 22. Figures 15 and 16 show an inside comer having an angle, and Figures 17 and 18 show an inside comer with a rounded or bullnose construction. Figures 19 and 20 show an outside comer having an angle, and Figures 21 and 22 show an outside comer with a bullnose shape. These comers are attached to the framing of the wall by their rear surfaces 108 and/or flanges

112 as described above for Figure 8. The comer surface 1500 extending between the front surfaces 106 in Figures 15, 16, 19, and 20 forms an angle and is capable of flexing through a small angular range of motion. The comer surface 1500 extending between the front surfaces 106 in Figures 17, 18, 21, and 22 is arcuate, forming an arcuate bullnose comer that is also flexible through a 'small range of motion. A ramp area 1502 lies between the comer surface 1500 and the front surface 106. A number of perforations 1504 are ' found within the front surfaces 106 and facilitate the application of joint compound or texturizing material.

Another example of the present invention is illustrated in Figures 23 through 25. Figure 23 shows an embodiment of the drywall comer fmishing device that is adjustable so that the device can be used with drywall panels of any width. As in the embodiment illustrated in Figures 1 and 2, the adjustable embodiment shown in Figure 23 comprises two wings 102, 104 attached by a center joint 100. The wings 102, 104 have a front surface 106 and a rear surface 108 held apart by a plurality of struts 206, as can be seen in Figure 24. The edge 202 of the rear surface 108 extends past the edge 200 of the front surface 106, leaving a space 114 between the edges 200, 202. The distal portion 204 of the front surface 106 tapers toward the distal portion 2304 of the rear surface 108, as shown in Figure 24. An expandable joint 2302 is placed between the distal portion 204 of the front surface 106 and the distal portion 2304 of the rear surface 108. A flexible joint 2300 is found at the proximal end of the distal portion 2304 of the rear surface 108. The flexible joint 2300 is preferably arcuate, but it is to be expressly understood that any joint shape, such as V-shaped, U-shaped, C-shaped, etc., can be used that allows the distal portion 2304 of the rear surface 108 to flex at the flexible joint 2300.

Drywall panels are conventionally supplied in predetermined widths, for example, and not meant to be inclusive, K inch, Vi inch, and Y% inch widths, etc. Rather than use a separate drywall comer finishing device for every predetermined thickness of drywall panel, one can use the embodiment of the drywall comer finishing device illustrated in Figures 23 through 25 to conform to any width of drywall panel, as shown in Figure 25. Figure 25(a) illustrates the drywall comer finishing device in the resting position. When a ' drywall panel 2500 is inseπed into the space 1 14 between the edges 200. 202. as shown in Figure 25(b), the edges 200, 202 move apart, as illustrated by arrows 2306, to accommodate the width of the drywall panel 2500.

As the edges 200, 202 move apart, the expansion joint 2302 opens and the flexible joint 2300 adjusts to enable the distal portions 204 and 2304 to move apart as far as necessary to enable insertion of the edge of the drywall panel 2500. This embodiment of the drywall comer finishing device can be used for drywall panels that are thicker than the thickness of the device. The expansion joint 2302 maintains tension on the distal portions 204 and 2304, which aids in maintaining close contact between the drywall panel 2500 and the distal portions 204, 2304 of the drywall comer finishing device. It is to be understood that types of expansion joints 2302 other than that illustrated in Figs. 23 - 25 can be used in the present invention and that the present invention includes all types and designs of joints that provide the above-described expansion and tension. The above disclosure sets forth a number of embodiments of the present invention. Other arrangements or embodiments, not precisely set forth, could be practiced under the teachings of the present invention and as set forth in the following claims.

Claims

1. A finishing device for use in forming a joint or a corner between two panels of drywall having edges of a predetermined thickness, said finishing device comprising: a flexible joint extending along a predetermined axis; two wings connected to and extending outwardly in a diverging relation from said flexible joint to form a corner having an adjustable angle, said wings having a distal edge parallel to said predetermined axis, said wings having a front surface and a rear surface, said front and rear surfaces being spaced apart in largely parallel relationship, said front and rear surfaces extending outwardly beyond said distal edge of said device and having a space therebetween, and an expansion joint extending between said front surface and said rear surface for adjusting the size of said space to fit said drywall panel edge thickness.

2. The drywall comer finishing device of claim 1 wherein said front surface tapers toward said rear surface.

3. The drywall corner finishing device of claim 1 further comprising a plurality of struts extending between said front surface and said rear surface.

4. The drywall corner finishing device of claim 1 wherein said outward extension of said rear surface provides a flange for attaching said finishing device to framing.

5. The drywall corner finishing device of claim 1 wherein said finishing device can be folded to a plurality of angles at said flexible joint so as to fit inside corners having a plurality of angles at said flexible joint so as to fit inside corners having a plurality of angles.

6. A drywall corner finishing device for use in forming a joint or corner between two drywall panels having edges of a predetermined thickness, said device comprising: an arcuate joint extending along the center longitudinal axis of said finishing device; two wings connected to and extending outwardly in diverging relation from said arcuate joint, said wings having a distal edge parallel to said center axis, said wings having a front surface and a rear surface, said front and rear surfaces being spaced apart in largely parallel relationship, said front and rear surfaces extending outwardly beyond said distal edge of said device and having a space therebetween; an expansion joint for adjusting the size of said space between said front surface and said rear surface to said drywall panel edge thickness; a flexible joint in said rear surface; and a plurality of struts interposed between said front surface and said rear surface.

7. The drywall co er finishing device of claim 6 wherein said front surface tapers toward said rear surface.

8. The drywall corner finishing device of claim 6 wherein said outward extension of said rear surface provides a flange for attaching said finishing device to framing.