Patent Publication Number: US-8984823-B2

Title: Wall corner strip

Description:
BACKGROUND OF THE PRESENT INVENTION 
     1. Field of Invention 
     The present invention relates to construction field, and more particularly to a wall corner strip adapted to make a right-angle wall corner. 
     2. Description of Related Arts 
     The traditional wall corners (mainly refer to indoor corners and the arris of the outer wall) of a building are needed to be right angle. During the construction process, workers make wall corners only by general tools and these right angles whether right or not mainly depends on the workers&#39; skill and experiment. Therefore, the existing way to make right-angle corners is difficult to meet requirement. The wall corners obtained from the existing way are not formed by straight surfaces, are not good appearance, and are easy to damage by a careless collision. In addition, the existing way also has the disadvantages of wasting of labor, time and material. 
     Chinese Patent Application with a Publication Number. CN101126280A, titled “Corner-protective strip special for mud work” introduces a corner-protective strip which includes two corner-protective boards and an edge provided on the outer side of the butt joint of two corner-protective boards. But this strip has no inflexed hook and no reinforced ridge, so it does not have the function to be embedded into wall, and it is easy deformation, and lacks a structure combined with mortar. That is, this strip is easy to fall off, and does not have an effect on protecting corner. Therefore, it has no utility. 
     Another Chinese Patent Application with a Publication Number. CN2234475Y, titled “Datum strip for whitewashing” introduces a datum strip includes a corner board, an adjustable board, a plurality of reinforced ridges, and an arc supporting mandrel, wherein the corner board and the adjustable board are cross-connected with each other, and the arc supporting mandrel is positioned in an angle between the corner board and the adjustable board. This datum strip has reinforced ridges, but also does not have inflexed hook. So it is it does not have the function to be embedded into wall as well. In addition, during construction face bricks must cover on the external surface of the datum strip. So the datum strip is mainly used for a corner covered with face bricks, since it is especially used with face bricks for decoration. Due to its limitation, this datum strip can not be used for common wall bodies with large area, so it dose not have utility. 
     Another Chinese Patent Application with a Publication Number. CN2453071Y, titled “Wall molding strip” introduces a having a similar structure with above applications, so it is has the same problems. 
     In summary, the public techniques in this field have obvious deficiencies and they can not achieve desirable effects and meet the practical demands. Due to less utility of the public techniques, a novel technique is needed to satisfy the construction requirements. 
     SUMMARY OF THE PRESENT INVENTION 
     A main object of the present invention is to provide a wall corner strip which is made of a hard plastic material having excellent elasticity and anti-deformation capability (such as ABS). The wall corner strip has some special structures such as inflexed hooks and gradually increasing thickness, which make sure the wall corner strip dose not deform and drop, and help the wall corner strip to be firmly fixed on the wall corner and be combined with the wall corner into one body. That is, the wall corner strip of the present invention has met the requirement for making a right angle wall corner, at same time, it has overcome the defects existed in the Chinese Patent Applications with Publication Number. CN101126280A, Publication Number. CN2234475Y and Publication Number. CN2453071Y. 
     Accordingly, in order to accomplish the above objects, the present invention provides a wall corner strip which comprises a longer board with a longer width and a shorter board with a shorter width, wherein a first side of the longer board and a first side of the shorter board are connected together to form a right angle between the longer external surface of the longer board and the shorter external surface of the shorter board, and an inner angle between the longer internal surface of the longer board and the shorter internal surface of the shorter board. The wall corner strip further comprises a solid protruding edge extended outward from the connecting part of the first side of the longer board and the first side of the shorter board. The longer board has an inflexed hook extended inwardly from a second side of the longer board to form an inner inflexed angle, in the same way, the shorter board also has an inflexed hook extended inwardly from the second side of the shorter board to form an inner inflexed angle. 
     Preferably, both thicknesses of the longer board and the shorter board are increased gradually from the first sides of the longer board and the shorter board to the second sides of the longer board and the shorter board respectively so that the inner angle is less than 90° and the inner inflexed angles are larger than 90° 
     Preferably, the longer board and the shorter board further have at least one reinforced ridge extended outward from their external surfaces. 
     The longer board and the shorter board both have a plurality of through holes with various shapes provided therein. 
     The wall corner strip is made of hard plastic with excellent elasticity. 
     The protruding edge has a thickness of 2 mm and a width of 4 mm. Both the first sides of the longer board and the shorter board have a thickness of 1.2 mm, and both the second sides of the longer board and the shorter board have a thickness of 2 mm. The longer board has a width of 24 mm, and the shorter board has a width of 18 mm. 
     The benefits of the present invention are that the present invention is obviously different from the existing technologies in structure, function and performance. The wall corner strip has simple structure, anti-deformation capacity and good adhesion. To form a wall corner with the wall corner strip makes sure the wall corner is straight and strong. And the wall corner strip makes the construction procedure is material saving, labor saving, time saving, and not afraid of impact and collision. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view of a wall corner strip according to a preferred embodiment of the present invention. 
         FIG. 2  is a top view of the  FIG. 1 . 
     
    
    
     In the drawings,  1  wall corner strip,  11  inflexed hook,  12  reinforced ridge,  13  solid protruding edge,  14  through hole,  15  inner angle,  16  inner inflexed angle,  17  shorter board,  17   a  shorter internal surface  17   c  shorter external surface,  171  first end of the shorter board,  172  second end of the shorter board,  18  longer board,  18   b  longer internal surface,  18   c  longer external surface,  181  first end of the longer board,  182  second end of the longer board,  19  outer inflexed angle. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A further disclosure of the present invention will be described in the following with reference to the drawings. 
     Embodiment: 
     Referring to  FIG. 1  and  FIG. 2  of the drawings, a wall corner strip  1  adapted to form a right angle wall corner is illustrated. The wall corner strip  1  is an elongated body with a length of 2.5 to 3.5 m, wherein the length of the wall corner strip  1  is determined according to the length of the wall. The cross section of the wall corner strip  1  is two unequal sides. 
     The wall corner strip  1  comprises a longer board  18  with a longer width and a shorter board  17  with a shorter width, wherein a first end  181  of the longer board  18  and a first end  171  of the shorter board  17  are connected together to form a right angle between the longer external surface  18   c  of the longer board  18  and the shorter external surface  17   c  of the shorter board  17 , and an inner angle  15  between the longer internal surface  18   b  of the longer board  18  and the shorter internal surface  17   a  of the shorter board  17 . 
     The wall corner strip  1  further comprises a solid protruding edge  13  extended outwardly from the connecting part of the first end  181  of the longer board  18  and the first end  171  of the shorter board  17 . 
     The longer board  18  has an inflexed hook  11  extended inwardly from a second end  182  of the longer board  18  to form an outer inflexed angle  19  of 90° between the longer external surface  18   c  and the inflexed hook  11 , and an inner inflexed angle  16  between the longer internal surface  18   b  and the inflexed hook  11 . In the same way, the shorter board  17  also has an inflexed hook  11  extended inwardly from the second end  172  of the shorter board  17  to form an outer inflexed angle  19  of 90° between the shorter external surface  17   c  and the inflexed hook  11 , and an inner inflexed angle  16  between the shorter internal surface  17   a  and the inflexed hook  11 . 
     According to the preferred embodiment of the present invention, the longer board  18  has a width of 24 mm, and the shorter board  17  has a width of 18 mm. Each inflexed hook  11  has a thickness of 1.2 mm and a width of 2 mm. The solid protruding edge  13  has a thickness of 2 mm and a width of 4 mm. 
     Preferably, both thicknesses of the longer board  18  and the shorter board  17  are increased gradually from the first ends  181  and  171  of the longer board  18  and the shorter board  17  to the second ends  182  and  172  of the longer board  18  and the shorter board  17  respectively. Therefore, the inner angle  15  is less than 90° and the inner inflexed angles  16  are larger than 90° , so as to enhance the tensile strength of the inflexed hooks  11 , and make it not easy to deform. According to the preferred embodiment of the present invention, both the first ends of the longer board  18  and the shorter  17  have a thickness of 1.2 mm, and both the second ends of the longer board  18  and the shorter board  17  have a thickness of 2 mm. 
     Preferably, the longer board  18  further has at least one reinforced ridge  12  extended outwardly from the longer external surface  18   c  of the longer board  18 . Similarly, the shorter board  17  further has at least one reinforced ridge  12  extended outwardly from the shorter external surface  17   c  of the shorter board  17 . Furthermore, the longer board  18  has a plurality of through holes  14  with various shapes provided therein, and the shorter board  17  also has a plurality of through holes  14  with various shapes provided therein. These through holes  14  are adapted to help the wall corner strip  1  to fix with the cement and mortar. 
     Producing Method 
     The wall corner strip  1  is made of acrylonitrile butadiene styrene (ABS) resin or other hard plastic material having excellent elasticity. The method of producing the wall corner strip  1  comprising the step of integratedly forming the wall corner strip  1  by a prefabricate mold. 
     The longer board  18  and the shorter board  17  of the wall corner strip  1  have different widths. Due to such a structure as recited above, the external forces acted on the wall corner strip  1  would not be in a line, so that the tensile strength of the wall corner strip  1  is enhanced. 
     Using Method 
     A using method of the wall corner strip  1  comprising the steps of: 
     placing the wall corner strip  1  on a wall corner; 
     embedding the inflexed hooks  11  of the longer board  18  and the shorter board  17  into the bottom mortar of the wall corner, due to the gradually increasing thicknesses of the longer board  18  and the shorter board  17 , the mortar filled in the wall corner strip  1  shapes an inverted triangle, so as to enhance the stability of the inflexed hooks  11 , and then to fix the wall corner strip  1  on the wall corner firmly; 
     applying mortar to the wall corner strip  1 , wherein the mortar enters into the through holes  14 ; 
     smoothing mortar on the wall corner strip  1  by a wooden board, then a right-angle wall corner is obtained. 
     Therefore, to form a wall corner with the wall corner strip  1  makes sure that the wall corner is straight, strong and good appearance. 
     Statement 
     Two test reports are provided herewith to illustrate novelty, nonobviousness and utility of the present invention, and the two test reports are both made on Feb. 23, 2010, by an agency authorized and designated by Hong Kong Government. See Appendix A and Appendix B. 
     The Appendix A titled “REPORT ON PULL OUT TEST OF PLASTIC ANGLE DEAD” shows that under an applied force of 1050 Newton, the sample of plastic angle bead (wall corner strip  1  in the present invention) has no visible damage. 
     The Appendix B titled “REPORT ON DETERMINATION OF SURFACE DAMAGE BY SMALL HARD BODY IMPACT” shows that under an impact energy of 10 Nm (the most level of the impact energy), that is, even through knocked by a heaviest hammer, there is only slight deformation of plastic edge (the longer board  18  and the shorter board  17  of the wall corner strip  1  in the present invention) being observed. 
     Therefore, the wall corner strip  1  of the present invention completely meets architectural requirements, and has obtained international certifications. It has been comprehensively applied in construction projects. 
     Comparing the present invention with the existing technologies, it is obviously to tell the differences therebetween, either in whole or in part. Furthermore, the two test reports certify that the present invention has brought unexpected results, and has prominent novelty, nonobviousness and utility.