Abstract:
A dry wall tape having a curved center section, reversely curved intermediate sections and outwardly tapering wings terminating in a thin edge. The tape can be used on inside and outside corner joints to obtain a straight line. Preferably the tape has triangular cut outs in the wings and removable end strips along the outer edges of the tape to facilitate taping of curved corners.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to dry wall tapes and particularly relates to a novel dry wall plastic tape which is suitable for application to inside and outside corners of coffered ceilings, bay windows, and any other angular dry wall application. This invention is also applicable for use on curved openings, arched dry wall openings and curved dry wall walls. 
     Currently it is very difficult to form a straight line along inside corners of rooms constructed with dry wall board. There is available beaded tape which is suitable for use on outside corners, but it takes a skilled and patient craftsman to form a uniformly straight line on an inside corners, such as are found in coffered ceilings and bay windows, and along curved arches and arched openings. 
     Accordingly, it is a principal object of this invention to provide a dry wall plastic tape which can be used for both inside and outside corners as well as being usable for curved or arched openings. It is a principal object of this invention to provide a dry wall tape which will allow the person taping to rapidly form a straight line on an inside corner and which tape can also be applied to outside corners. It is still a further object to provide such a tape which also is applicable to curved openings such as are found on rounded half walls, curved stair wells, and arched dry wall openings. 
     These and other objects and advantages will become apparent hereinafter. 
     SUMMARY OF THE INVENTION 
     The present invention comprises a tape having an outwardly arched center section and reversely curved intermediate sections with laterally extending relatively flat wings along the side edges of the tape. 
     The invention also consists in the parts and in the arrangements and combinations of parts hereinafter described and claimed. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     In the accompanying drawings which form part of the specification and wherein like numbers and letters refer to like parts wherever they occur 
     FIG. 1 is an end elevational view of one form of this invention; 
     FIG. 2 is a top plan view of the invention shown in FIG. 1.; 
     FIG. 3 is a fragmentary enlarged end elevational view of a second form of the invention; 
     FIG. 4 is a top plan view of the form of the invention shown in FIG. 3; 
     FIG. 5 is a fragmentary end elevational view of the tape applied to an outside corner; 
     FIG. 6 is a fragmentary end elevational view of the tape applied to an inside corner; and 
     FIG. 7 is a fragmentary perspective view of the tape of FIGS. 1 and 2 applied to an arched opening. 
     FIG. 8 is a fragmentary perspective view of the tape applied to a rounded wall; and 
     FIG. 9 is a fragmentary enlarged perspective view of the tape applied to a curved corner joint. 
    
    
     DETAILED DESCRIPTION 
     The preferred form of the invention is shown in FIGS. 1 and 2 and the tape 10 comprises an arched center section 11 and reversely arched intermediate sections 12 and 13 connecting the arched center section 11 with outwardly extending wings 14 and 15. The arched center section 11 preferably is provided with internal serrations 16 on the inside of the arch to facilitate bending. This is shown in more detail in FIG. 3. 
     The top of the arch section 11 preferably is about 1/16&#34; to about 3/32&#34; above the plane of the wings 14, 15 as identified by the line A--A in FIG. 3. This distance is denoted by the letter &#34;x&#34;. The outermost parts of the intermediate sections 12, 13 preferably are about 1/16&#34; to about 3/32&#34; below the line A--A. This distance is identified by the letter &#34;z&#34; in FIG. 3. The intermediate sections 12, 13 are about 5/64&#34; to about 3/32&#34; in width as shown by the letter &#34;a&#34; in FIG. 3. The arch center section 11 is about 3/32&#34; to about 1/8&#34; in width as shown by the letter &#34;b&#34; in FIG. 3. 
     The outwardly depending and diverging wings 14 and 15 preferably are provided with V-shaped notches 17 (FIG. 2) which have their apex 18 at the point of connection to the intermediate sections 12 and 13 and their widest part is most remote from the center arched section 11. The notches 17 thus define adjacent triangular solid members 14a and 15a on the respective wings 14 and 15. 
     The notches 17 in each depending wing 14 and 15 are staggered so that the apex of a notch 17 on wing 14 is aligned with approximately the center of the triangularly shaped solid member 15a of the opposed wing 15. Thus the wings 14 and 15 are formed of a continuous series of triangularly shaped pieces 14a, 15a which are connected at their widest part to the intermediate sections 12 and 13. At the point on the triangular pieces 14a, 15a which is most remote from the center section 11 and along the outer edges of the tape 10 are releasible and removable tear strips 20, 21. The purpose for the tear strips 20, 21 is to allow the notches 17 to separate when the tape 10 is applied to an arched or rounded opening or corner as shown in FIGS. 7-9. The pieces 15a on the inner side of the curved corner gather together as also seen in FIG. 9. 
     Preferably the wings 14 and 15 are about 3/64&#34; to about 1/16&#34; in thickness where they join the intermediate sections 12, 13, and taper outwardly rom this point of connection toward their connection with the tear strips 20 and 21. The tear strips 20, 21 preferably are about 1/64&#34; to about 1/32&#34; in thickness. Thus, it is easier to provide a smooth finish to the joint because the wings 14, 15 are very thin and get thinner the further they extend away from the corner. 
     The wings 14, 14a are marked with suitable indicia 22 each foot and are scribed every inch. These markings are on the tear strips 20, 21 in the form of the invention shown in FIGS. 1 and 2. 
     The wings 14, 15 preferably are about 11/2&#34; to about 13/4&#34; in width and the tear strips 20, 21 are preferably about 1/16&#34; to about 3/32&#34; in width. The sold triangular members 14a, 15a preferably have a width of about 3/16&#34; to about 1/4&#34; at their point of intersection with the intermediate members 12, 13. 
     The tape 10a shown in FIGS. 3 and 4 is applicable to straight line joints and is not designed for use with curved openings. In this tape 10a, the wings 30 and 31 are solid and do not have V-shaped grooves or the tear strip. The wings 30, 31 preferably are tapered however and have the same dimensions as hereinbefore discussed for the tape 10. The wings 30, 31 have indentations, serrations or perforation 33 or other roughening effects, such as that caused by chemical or physical etching randomly positioned on the outer surface to help the dry wall compound adhere to the tape. 
     The tapes 10, 10a preferably are made of an extruded polymeric material. The tape should have some rigidity, and should be deformable to hold the shape it is formed into on the corner and also should adhere to the dry wall compound. 
     FIG. 5 shows the tape 10 applied to an outside joint and in the process of applying the tape 10, dry wall compound is applied to the joint before the tape 10 is placed along the joint. After the tape 10 has been placed along the joint so that the center section 11 protrudes outwardly from the joint, the dry wall compound is applied to the outside of the tape with a tape knife. The tape knife is guided on the protruding center section 11 so that a straight line is formed at the center of the joint. The tape knife, of course, also feathers the joint compound out over the free edge of the tape wings 14 and 15. 
     FIG. 6 shows the tape 10 applied to an inside joint. In this application, the center arch 11 is positioned adjacent to the joint and the intermediate sections 12 and 13 protrude outwardly away from the joint. In applying the tape 10 to the inside joint, the joint compound is first applied and then the tape 10 is positioned so that the center member 11 is adjacent to the joint. The joint compound is then smoothed and formed into a straight line by guiding the taping knife on the protruding intermediate sections 12 and 13. 
     FIGS. 7-9 show the tape 10 of FIGS. 1 and 2 applied to curved joints. The pull away sections 20, 21 of the tape 10 are removed from that part of the tape 10 which is curved around the joint, so that it facilitates the V-shaped grooves 17 opening up or closing depending on whether they are inside or outside the curve. The taping proceeds in a similar fashion to that previously described depending on whether the curve is an inside or outside curve. 
     This invention is intended to cover all changes and modifications of the example of the invention herein chosen for purposes of the disclosure which do not constitute departures from the spirit and scope of the invention.