PATENT ABSTRACT
A utility corner shelf bracket which enables easy installation and removal, which are done quickly and without requiring tools, of a utility corner shelf bracket, and placing a shelf upon it, and which it based on bows which are capable of bending on one plane and durable to loads perpendicular to this plane and a tensioning system which enables adjustment to the wall corner prior to installation and fastening to the wall during installation.

PATENT DESCRIPTION
REFERENCE TO CROSS-RELATED APPLICATION 
     This application is a Continuation-in-Part of U.S. application Ser. No. 13/074,032 filed Mar. 29, 2011, which is a Continuation-in-Part of PCT/IL2009/001061, filed Nov. 12, 2009. 
     This application claims priority benefits from U.S. application Ser. No. 13/074,032 filed Mar. 29, 2011, which claims priority benefits from PCT/IL2009/001061, filed Nov. 12, 2009, which claims priority benefits from U.S. Provisional Application No. 61/117,251, Filed on Nov. 24, 2008, and from U.S. Provisional Application 61/218,948, filed on Jun. 21, 2009, the full disclosures of which are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a shelf bracket, and, more particularly, to a utility corner shelf bracket. 
     BACKGROUND OF THE INVENTION 
     The need for installing shelves at intersections of structure walls or ends of furniture, which form corners, has existed for many generations. Many solutions are based on placing a shelf on a bracket, which has been fixed to the corner walls at the desired height. 
     A corner bracket is described in U.S. Pat. No. 1,325,143 (1919) of Conterio, which is incorporated by reference for all purposes as if fully set forth herein. 
     A shelf assembly and a support bracket are described in U.S. Pat. No. 4,555,082 (1985) of Sack, et al. which is incorporated by reference for all purposes as if fully set forth herein. This solution is supposed to overcome the limitations of previous solutions, including that of Conterio. These limitations also include being assembled of many separate components, whose assembly is expensive and time consuming, while also being aesthetically unpleasant to the sight. 
     However, even the solution of Sack, et al. has its faults, particularly the need for mounting means, such as nails or screws that are partially inserted into a pair of walls that form a corner before the installment of the shelf assembly. 
     None of the prior art devices enable easy installment and removal, which are done quickly and without requiring tools, of a utility corner shelf bracket, upon which a corner shelf is mounted. 
     There is therefore a need for a utility corner shelf bracket which enables easy installation and removal, which are done quickly and without requiring tools, and upon which a shelf can be mounted, and it would be advantageous if additional accessories could be engaged, for the purpose of bearing loads. 
     SUMMARY OF THE INVENTION 
     An embodiment of the present invention is described herein below in which a utility corner shelf bracket can be easily installed and removed, quickly and without requiring tools, and a shelf can be mounted upon it. The utility corner shelf bracket according to the present invention is composed of two external arced elastic bows and an internal arced elastic bow. Upon the external surface of one of the external elastic bows are insertion means and pulling means. Installation of the utility corner shelf bracket according to the present invention is an extremely simple process which includes manual tensioning, similar to tensioning a bow prior to shooting an arrow, placing it where it should be in the corner, releasing the manual tension, and applying pulling force between the bows with the pulling means, causing the insertion means to be inserted into the walls. Afterwards, all that remains to be done is to place a corner shelf on the utility corner shelf bracket. Removal is done by performing similar actions in reverse order. These actions can be performed in a matter of seconds. 
     According to the present invention there is provided a utility corner shelf bracket ( 100 ) including: a first bow ( 11 ), the first bow ( 11 ) including: two first bow wings ( 11   b ); a first bow arc ( 11   a ), wherein each one of the first bow wings ( 11   b ) is operatively connected to the first bow arc ( 11   a ); at least one nail ( 18 ) operatively connected to each one of the first bow wings ( 11   b ); a second bow ( 12 ) operatively connected to the first bow ( 11 ); and a pulling assembly ( 20 ), having a length, operatively connected to the second bow ( 12 ), wherein an operation of the pulling assembly ( 20 ) creates a pulling force on the second bow ( 12 ), and wherein the second bow ( 12 ) applies force to the two first bow wings ( 11   b ), wherein the utility corner shelf bracket ( 100 ) is adapted to be combined with at least one insert ( 80 ). 
     According to another feature of the present invention each one of the two first bow wings ( 11   b ) includes at least one first bow window ( 11   bc ), wherein each one of the first bow window ( 11   bc ) is configured to contain a an insert arm ( 82 ). 
     According to still another feature of the present invention the pulling assembly ( 20 ) includes: a turnbuckle sleeve ( 21   c ); a central rod ( 27 ), having two ends, wherein one of the ends of the central rod ( 27 ) is disposed on the second bow ( 12 ), and wherein one of the ends of the central rod ( 27 ) is engaged with the turnbuckle sleeve ( 21   c ); and a screwing rod ( 22   a ) having two ends wherein one end of the screwing rod end is engaged with the turnbuckle sleeve ( 21   c ). 
     According to still another feature of the present invention the utility corner shelf bracket ( 100 ) further including: a T rod ( 31 ) disposed on the screwing rod ( 23   c ); and two side rods ( 28 ) wherein each one of the side rods ( 28 ) is disposed on the T rod ( 31 ), and wherein a rotation of the turnbuckle sleeve ( 21   c ) changes the length of the pulling assembly ( 20 ). 
     According to still another feature of the present invention the utility corner shelf bracket ( 100 ) further including: at least one insert ( 80 ), wherein the insert ( 80 ) is inserted with the utility corner shelf bracket ( 100 ). 
     According to still another feature of the present invention the at least one insert ( 80 ) includes: an insert body ( 81 ); and an adhesive layer ( 18   b ) attached to the insert body ( 81 ). 
     According to still another feature of the present invention the at least one insert ( 80 ) includes: an insert body ( 81 ); and at least one nail ( 18 ) attached to the insert body ( 81 ). 
     According to the present invention there is provided an insert ( 80 ), including: an insert body ( 81 ); and at least one inserting means ( 89 ) attached to the insert body ( 81 ), wherein the insert ( 80 ) is adapted to be inserted with a utility corner shelf bracket ( 100 ). 
     According to another feature of the present invention the inserting means ( 89 ) includes: an insert arm ( 82 ); and an insert push button ( 83 ) having an insert stair ( 84 ), the insert push button ( 83 ) is attached to the insert arm ( 82 ). 
     According to still another feature of the present invention the insert ( 80 ) further including: at least one nail ( 18 ), attached to the insert body ( 81 ). 
     According to still another feature of the present invention the insert ( 80 ) further including: an adhesive layer ( 18   b ), attached to the insert body ( 81 ). 
     According to the present invention there is provided a utility corner shelf bracket ( 100 ) including: a first bow ( 11 ), the first bow including: a first bow arc ( 11   a ); two first bow wings ( 11   b ), wherein each one of the first bow wings ( 11   b ) is operatively connected to the first bow arc ( 11 ); two pressing handles ( 36 ), wherein each one of the pressing handles ( 36 ) is disposed on one of the first bow wings ( 11   b ); and a second bow ( 12 ) having two ends ( 12   a ), wherein each one of the ends ( 12   a ) of the second bow ( 12 ) is disposed on an element of the utility corner shelf bracket ( 100 ) selected from a group consisting of the first bow wings ( 11   b ), and the pressing handles ( 36 ). 
     According to another feature of the present invention the utility corner shelf bracket ( 100 ) is made as a one integral piece of an elastic material. 
     According to still another feature of the present invention the utility corner shelf bracket ( 100 ) further including: at least one nail ( 18 ) disposed on each one of the first bow wings ( 11   b ). 
     According to still another feature of the present invention the utility corner shelf bracket ( 100 ) further including: at least one strengthening rib ( 30 ) disposed on one of the first bow wings ( 11   b ). 
     According to still another feature of the present invention the utility corner shelf bracket ( 100 ) further including: at least one hanging device ( 37 ) disposed on the second bow ( 12 ). 
     According to still another feature of the present invention the first bow arc ( 11   a ) and the second bow ( 12 ) are springs, wherein in a free state the first bow arc ( 11   a ) has a bow arc bending angle (C) of at most ninety degrees and wherein the second bow ( 12 ) has a second bow bending angle (D) of at least forty degrees. 
     According to still another feature of the present invention the utility corner shelf bracket ( 100 ) is made of a polymer. 
     According to still another feature of the present invention the utility corner shelf bracket ( 100 ) further including: two nail protectors ( 50 ), wherein each one of the two nail protectors ( 50 ) is connected to another one of the first bow wings ( 11   b ) by a protector connector ( 50   a ). 
     According to still another feature of the present invention the utility corner shelf bracket ( 100 ) further including: (e) two protective wings ( 60 ), wherein each one of the protective wings ( 60 ) has at least one protective wing hole ( 60   a ), wherein each one of the protective wings ( 60 ) has a protective wing connecting end ( 60   b ), wherein each one of the protective wing connecting ends ( 60   b ) is connected to the first bow ( 11 ), wherein the connection is configured to produce a moment force which tends to couple the protective wing ( 60 ) to another one of the first bow wings ( 11   b ); and (f) two protective wing supports ( 61 ), wherein each one of the protective wing supports ( 61 ) has a protective wing support first end ( 61   a ), and a protective wing support second end ( 61   b ) wherein each one of the protective wing support first ends ( 61   a ) is connected to another one of the two pressing handles ( 36 ), wherein each one of the protective wing supports ( 61 ) is made of an elastic material, wherein each one of the pressing handles ( 36 ) has a handle groove ( 36   a ), wherein each one of the protective wing support second ends ( 61   b ) is configured to prevent another one of the protective wings ( 60 ) to move in with a tendency for coupling the protective wing ( 60 ) to another one of the first bow wing ( 11   b ), if there is applied an external force on the protective wing supports ( 61 ) and to gather, at least partially, into the handle grooves ( 36   a ) and cease from preventing another one of the protective wings ( 60 ) to move in a tendency for coupling the protective wing ( 60 ) to another one of the first bow wings ( 11   b ), if an external force is applied on the protective wing supports ( 61 ). 
     According to still another feature of the present invention the utility corner shelf bracket ( 100 ) further including: two first integral pivots ( 73 ), wherein each one of the two first integral pivot ( 73 ) is attached to another one of the first bow wings ( 11   b ); two shield arms ( 70 ), wherein each one of the two shield arms ( 70 ) is attached to another one of the two first integral pivots ( 73 ); two second integral pivots ( 73   a ), wherein each one of the two second integral pivots ( 73   a ) is attached to another one of the two shield arms ( 70 ); and two nails shield ( 70 ) wherein each one of the two nails shield ( 70 ) is attached to another one of the two second integral pivots ( 73   a ). 
     According to still another feature of the present invention each one of the two nail shields ( 70 ) includes: a shield front wall ( 71 ); and two shield side walls ( 72 ), wherein each one of the two shield side walls ( 72 ) is attached to the shield front wall ( 71 ), and wherein at least one of the two shield side walls ( 72 ) has a side wall slot ( 72   a ). 
     According to still another feature of the present invention the utility corner shelf bracket ( 100 ) further including: at least one first bow first pin ( 11   e ) attached to each one of the first bow wing; and at least one first bow second pin ( 11   f ) attached to each one of the first bow wing. 
     According to still another feature of the present invention at least one of each of the two shield side walls ( 72 ) of the nails shield has an shield stair ( 94 ). 
     According to still another feature of the present invention at least one of the first bow first pin ( 11   e ) is located inside one of the wall slots ( 72   a ). 
     According to still another feature of the present invention the utility corner shelf bracket ( 100 ) further including: at least one nail ( 18 ) disposed on each one of the first bow wings ( 11   b ). 
     Additional objects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an isometric schematic illustration of an illustrative, exemplary first embodiment of a utility corner shelf bracket, according to the present invention. 
         FIG. 2  is a top schematic illustration of an illustrative, exemplary first embodiment of a utility corner shelf bracket, installed in a corner wall, according to the present invention. 
         FIG. 3  is an isometric schematic illustration of an illustrative, exemplary first embodiment of a utility corner shelf bracket, at a stage prior to installation, according to the present invention. 
         FIG. 4  is a top schematic illustration of an illustrative, exemplary first embodiment of a utility corner shelf bracket, in a corner wall, at a stage prior to installation, according to the present invention. 
         FIG. 5  is an isometric schematic illustration of an illustrative, exemplary first embodiment of a utility corner shelf bracket, and a shelf, at a stage prior to placing the shelf on the utility corner shelf bracket, according to the present invention. 
         FIG. 6  is a right side schematic illustration of an illustrative, exemplary first embodiment of a utility corner shelf bracket, and a shelf, at a stage following placing the shelf on the utility corner shelf bracket, according to the present invention. 
         FIG. 7 a    is a top view schematic illustration of an illustrative, exemplary second embodiment, first variant of a utility corner shelf bracket, according to the present invention. 
         FIG. 7 b    is an isometric view schematic illustration of an illustrative, exemplary second embodiment, first variant of a utility corner shelf bracket, according to the present invention. 
         FIG. 7 c    is a top view schematic illustration of an illustrative, exemplary second embodiment, variant of the utility corner shelf bracket and of two inserts, according to the present invention, upon which the section plane  7   f - 7   f  is marked 
         FIG. 7 d    is a top view schematic illustration of an illustrative, exemplary second embodiment, second variant of the utility corner shelf bracket, according to the present invention. 
         FIG. 7 e    is an isometric view schematic illustration of an illustrative, exemplary second embodiment, variant of the utility corner shelf bracket and two inserts, according to the present invention. 
         FIG. 7 f    is a schematic cross sectional view  7   f - 7   f  of the utility corner shelf bracket and of an insert, according to the present invention. 
         FIG. 7 g    is a top view schematic illustration of an illustrative, exemplary embodiment, of two inserts, according to the present invention. 
         FIG. 7 h    is an isometric view schematic illustration of an illustrative, exemplary embodiment, of two inserts, according to the present invention. 
         FIG. 7 i    is a front view schematic illustration of an illustrative, exemplary embodiment, of two inserts, according to the present invention. 
         FIG. 7 j    is a back view schematic illustration of an illustrative, exemplary embodiment, of an insert, according to the present invention. 
         FIG. 7 k    is a side view schematic illustration of an illustrative, exemplary embodiment, of two inserts, according to the present invention. 
         FIG. 8 a    is a top schematic illustration of an illustrative, exemplary third embodiment, first variant, of a utility corner shelf bracket, according to the present invention. 
         FIG. 8 b    is an isometric schematic illustration of an illustrative, exemplary third embodiment, first variant, of the utility corner shelf bracket, according to the present invention. 
         FIG. 8 c    is a top schematic illustration of an illustrative, exemplary third embodiment, first variant, of the utility corner shelf bracket, installed in a corner wall upon which is mounted a shelf, according to the present invention. 
         FIG. 8 d    is an isometric schematic illustration of an illustrative, exemplary third embodiment, first variant, of the utility corner shelf bracket, which is attached to a load, according to the present invention. 
         FIG. 8 e    is an isometric schematic illustration of an illustrative, exemplary third embodiment, second variant, of the utility corner shelf bracket having a protector connector, according to the present invention. 
         FIG. 8 f    is a top schematic illustration of an illustrative, exemplary third embodiment, third variant, of the utility corner shelf bracket, having a protective wing in open state, according to the present invention. 
         FIG. 8 g    is a top schematic illustration of an illustrative, exemplary third embodiment, third variant, of the utility corner shelf bracket, having a protective wing in closed state, according to the present invention. 
         FIG. 8 h    is an isometric schematic illustration of an illustrative, exemplary third embodiment, third variant, of the utility corner shelf bracket, having a protective wing in open state, according to the present invention. 
         FIG. 8 i    is an isometric schematic illustration of an illustrative, exemplary third embodiment, fourth variant, of the utility corner shelf bracket having two nail shields in a protective state according to the present invention. 
         FIG. 8 j    is an isometric schematic illustration of an illustrative, exemplary third embodiment, fourth variant, of the utility corner shelf bracket, having two nail shields in a nails exposed state according to the present invention. 
         FIG. 8 k    is an isometric schematic illustration of an illustrative, exemplary third embodiment, fourth variant, of the utility corner shelf bracket having two nail shields in an immediately after molding state according to the present invention. 
         FIG. 8 l    is a top view schematic illustration of an illustrative, exemplary third embodiment, fourth variant, of the utility corner shelf bracket having two nail shields in an immediately after molding state according to the present invention. 
         FIG. 8 m    is a top view schematic illustration of an illustrative, exemplary third embodiment, fourth variant, of the utility corner shelf bracket having two nail shields in a protective state according to the present invention. 
         FIG. 8 n    is a top view schematic illustration of an illustrative, exemplary third embodiment, fourth variant, of the utility corner shelf bracket having two nail shields in a safe state according to the present invention. 
         FIG. 8 o    is a top view schematic illustration of an illustrative, exemplary third embodiment, fourth variant, of the utility corner shelf bracket, having two nail shields in a pressed against corner walls state, according to the present invention. 
         FIG. 8 p    is a top view schematic illustration of an illustrative, exemplary third embodiment, fourth variant, of the utility corner shelf bracket having two nails shields in an installed on a corner walls state according to the present invention. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     The present invention is of a utility corner shelf bracket and of a method for its installation with a shelf in a corner wall, and a method of removing them from the corner wall. 
     The principles and operation of a utility corner shelf bracket according to the present invention may be better understood with reference to the drawings and the accompanying description. Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. 
     Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The materials, dimensions, methods, and examples provided herein are illustrative only and are not intended to be limiting. 
     To remove any doubt, note that the manner in which the elements of the present invention are described in the illustrations can be highly detailed, however is not in any way limiting the present illustration, but rather is for the purpose of clarification and furthering understanding. The present invention can be implemented in embodiments that differ from the specification given with regard to the illustration. 
     The following list is a legend of the numbering of the application illustrations:
           11  first bow     11   a  first bow arc     11   b  first bow wing     11   bb  first bow flap     11   bc  first bow window     11   bd  first bow wing outer surface     11   c  first bow extender     11   e  first bow first pin     11   f  first bow second pin     12  second bow     12   a  first end of a second bow     12   b  second end of a second bow     13   a  third bow (of first embodiment)     14  hinge     15  socket     16  first socket plate     17  second socket plate     18  nail     18   b  adhesive layer     19  support     20  pulling assembly     21   a  turnbuckle sleeve (of first embodiment)     21   c  turnbuckle sleeve (of second and third and embodiments)     22   a  first screwing rod     23   a  second screwing rod (of first embodiment)     23   c  second screwing rod (of second embodiments)     24  first nut     25  second nut     27  central rod     28  side rod     30  strengthening rib     31  T rod     36  pressing handle     36   a  pressing handle groove     37  hanging device     40  load     50  nail protector     50   a  protector connector     50   b  protector pin     50   c  first bow wing hole     60  protective wing     60   a  protective wing hole     60   b  protective wing connecting end     61  protective wing support     61   a  protective wing support first end     61   b  protective wing support second end     70  nail shield     71  shield front wall     72  shield side wall     72   a  side wall slot     73  shield arm     73   a  first integral pivot     73   b  second integral pivot     74  shield stair     80  insert     81  insert body     81   a  insert area     82  insert arm     83  insert push button     84  insert stair     85  insert outer surface     86  insert nail housing     87   a  insert outer side wall     87   b  insert inner side wall     88  insert back rail     89  inserting means     100   c  utility corner shelf bracket (second embodiment)     100   f  utility corner shelf bracket (third embodiment)     101  corner wall     102  corner shelf   F force       

     When the accompanying description of a specific illustration mentions an element not shown in that illustration or without numbering, its numbering is shown in parentheses, and can be found in one or more other illustrations. 
     Referring now to the drawings,  FIG. 1  is an isometric schematic illustration of an illustrative, exemplary first embodiment of a utility corner shelf bracket  100   a , (first embodiment), according to the present invention. 
     The utility corner shelf bracket  100   a  (first embodiment) includes a first bow  11  and a second bow  12 , connected to each other at their ends so as to enable angular movement between their ends around two hinges  14 , one at each end, which form a closed shape from top view. Each hinge  14  is assembled within a socket  15 , which can be an integral part of a first socket plate  16 , which is engaged with an additional socket, which can be an integral part of a second socket plate  17 , while the two first socket plates  16  are disposed near both ends of the first bow  11 , and the two second socket plates  17  are disposed near both ends of the second bow  12 . 
     In another possible embodiment, the sockets are integral parts of the first bow  11  and the second bow  12 . The first bow  11  and second bow  12  have arced shapes, while the center point of the first bow  11  is origin of a Cartesian axis system, whose axes X, Y, and Z, are in directions shown in the present illustration: the X axis is in the direction of the center point of the second bow  12 , the Y axis is to the left, in view from the origin, on a plane parallel to that on which the first bow  11  and second bow  12  are placed so that after assembly to a corner wall ( 101 ), assuming that its walls are vertical, it is essentially a horizontal plane, and the Z axis in this state is vertically downwards. The central part of first bow  11  has a first bow arc  11   a  and two first bow wings  11   b , each of which progresses to one of either end of first bow arc  11   a , and whose shape is planar after assembly to the corner wall ( 101 ), (if the wall is planar), as will be shown in  FIG. 2 . The external side of each first bow wing lib has several nails  18 , which are designated for insertion into the corner wall ( 101 ) after assembly, in order to prevent movement between the utility corner shelf bracket  100   a  (first embodiment), and the corner wall ( 101 ). In order to facilitate the prevention of movement, the external surface of each first bow wing lib can have a high friction coefficient, which can be achieved either by selection of the material and the processing of the surface, or by adding an external layer of a suitable material, such as a layer of rubber. 
     The first bow  11  and second bow  12  can be composed of various materials, such as aluminum, and have a good ability for bending on the XY plane, suitable for manual forces applied on a pulling assembly ( 20 ), while they are durable to loads in the direction of the Z axis which may be applied to the corner shelf  102  while it is mounted upon the utility corner shelf bracket  100   a  (first embodiment). 
     Inwards from the first bow  11  and second bow, is a third bow  13   a , (of the first embodiment), whose ends rest upon two supports  19 , each of which is disposed on the internal side of the first bow  11  for the purpose of transmitting forces from the first bow  11  and second bow  12 , which are generated at a certain point which will be described later on, by the pulling assembly  20 . Note that this form of force transmission from the third bow  13   a , (of the first embodiment), to the first bow  11 , is one viable option of several, and does not limit the present invention in any way. 
     The pulling assembly ( 20 ), one possible structure of which, and whose method of action, will be specified later on, includes a turnbuckle sleeve  21   a , with left and right hand internal threads on both ends, which can be rotated to the left or to the right, for purposes that will be specified later on, around axis X, with the rotation leftward in view from the origin, around axis X, marked in the present illustration with arrow ‘B’. 
       FIG. 2  is a top schematic illustration of an illustrative, exemplary first embodiment of a utility corner shelf bracket  100   a  (first embodiment), installed on a corner wall  101 , according to the present invention. 
     In this state, the angle ‘A’ formed between both of the first bow wings lib, equals the angle formed between both walls comprising the corner wall  101 , and the nails  18  are inserted in the walls. In this state, a corner shelf  102  can be placed upon the utility corner shelf bracket  100   a  (first embodiment). The angle ‘A’ is, in most cases, of 90 degrees, however the utility corner shelf bracket  100   a  (first embodiment), can also be installed in other values of this angle. 
     The pulling assembly  20 , which can apply pulling force, is disposed along the X axis, between the second bow  12 , and the third bow  13   a  (of the first embodiment), which applies forces F 3  on the first bow wings lib. This pulling also causes the second bow  12  to apply forces F 4  on the first bow wings lib. These force components fasten the first bow wings lib towards the two walls of the corner wall  101 . 
     The pulling assembly  20 , shown in the illustrations of the present patent application, includes two rods, a first screwing rod  22   a , with external threads in a first direction, and a second screwing rod  23   a , with external threads in a second direction. 
     The two rods are engaged with turnbuckle sleeve  21   a , namely are screwed into turnbuckle sleeve  21   a , which has left and right hand internal threads at both of its ends and ability to rotate left and right around the X axis, as shown by arrow ‘B’. 
     The turnbuckle sleeve  21   a  can be shaped as a cylinder with a closed wall or partial wall, as shown in the illustrations of the present application. 
     The first screwing rod  22   a  is connected to a second bow  12 , and the second screwing rod  23   a  is connected to a third bow  13   a  (of the first embodiment), through a hole in its center, and its location, according to one embodiment, can be adjusted by means of a first nut  24 , and a second nut  25 . In this manner, the operation of the pulling assembly  20 , which is done by means of rotation of the turnbuckle sleeve  21   a , in one direction, changing its length L, results in the first_rod  22   a  and the second screwing rod  23   a  moving towards one another, creating the pulling force described above, while rotation in the other direction causes the rods to move away from one another, and the pulling force is replaced by a pushing force which reverses the directions of forces F 3  and F 4 , thus decreasing the angle ‘A’ between the two first bow wings lib and therefore causing their moving away and the removal of the nails  18  from the walls. 
       FIG. 3  is an isometric schematic illustration of an illustrative, exemplary first embodiment of a utility corner shelf bracket  100   a  (first embodiment), at a stage prior to installation, according to the present invention. 
     At this stage, the installing person, who can be without any special expertise, uses both hands to tension the utility corner shelf bracket  100   a  (first embodiment), along the X axis, ensuring that the angle ‘A’ is small enough to bring close to the corner wall  101 . 
       FIG. 4  is a top schematic illustration of an illustrative, exemplary first embodiment of a utility corner shelf bracket  100   a  (first embodiment), installed at a corner wall  101 , at a stage prior to installation, according to the present invention. 
     Because angle ‘A’ is sufficiently small, the utility corner shelf bracket  100   a  (first embodiment), can be brought close to the corner wall  101 , as shown in the present illustration, for the purpose of installation. 
       FIG. 5  is an isometric schematic illustration of an illustrative, exemplary first embodiment of a utility corner shelf bracket  100   a  (first embodiment), and a corner shelf  102 , at a stage prior to placing the shelf  102  on the utility corner shelf bracket  100   a , (first embodiment), according to the present invention. 
       FIG. 6  is a right side schematic illustration of an illustrative, exemplary first embodiment of a utility corner shelf bracket  100   a  (first embodiment), and a corner shelf  102 , at a stage following placing the corner shelf  102  upon the utility corner shelf, according to the present invention. 
     The invention according to the present patent application is not limited to the installation of the utility corner shelf bracket  100   a  (first embodiment), in corners of vertical walls, and it can also be installed, for example, in a corner formed between a wall and a ceiling. 
     A method for installing a utility corner shelf bracket ( 100   a ) (first embodiment), and a corner shelf ( 102 ) at a corner wall includes the stages of:
         providing a utility corner shelf bracket ( 100   a ) (first embodiment)), and a shelf ( 102 );   tensioning the utility corner shelf bracket ( 100   a ) (first embodiment);   turning the turnbuckle sleeve ( 21   a ), until the nails ( 18 ) are sufficiently inserted into the walls; and   placing the corner shelf ( 102 ) upon the utility corner shelf bracket.       

     The method for removing a utility corner shelf bracket ( 100   a ) (first embodiment), and a corner shelf ( 102 ) from a corner wall includes the stages of:
         removing the corner shelf ( 102 ) from the utility corner shelf bracket ( 100   a ) (first embodiment);   turning the turnbuckle sleeve, until reaching extraction of the nails ( 18 ) from the walls; and   removing the utility corner shelf bracket ( 100   a ) (first embodiment) from the corner wall.       

     The following illustrations and the accompanying description specifies additional embodiments. 
     Many of the structural features and qualities typical of the first embodiment also apply to these additional embodiments. Various combinations of structural elements and features mentioned in the present patent application can serve for additional embodiments of the utility corner shelf bracket according to the present invention. 
       FIG. 7 a    is a top schematic illustration of an illustrative, exemplary second embodiment, first variant of the utility corner shelf bracket  100   c , according to the present invention. 
     The pulling assembly  20  of the present illustration includes a central rod  27  (of second), a turnbuckle sleeve  21   c  (of second embodiments), and a second screwing rod  23   c  (of second embodiments), whose end is connected to a T rod  31 , both of whose ends have shafts which are connected to two side rods  28 , as shown in the illustration. 
     The central part of first bow  11  has a first bow arc  11   a  and two first bow wings  11   b , each of which progresses to one of either end of first bow arc  11   a , and whose shape is planar after assembly to a corner wall ( 101 ) (if the wall is planar). 
     The internal wall of the first bow  11  has at least one support rod  32 , which prevents overextension, and thus protects the user&#39;s fingers. Each first bow wing lib on the internal wall is connected to a strengthening rib  30 , which provides additional resistance to bending and facilitates mounting up to a wall. 
     The first bow extenders  11   c  lie shown in the present illustration are of another possible top view shape, and as noted, are designated to increase the area of contact with the corner shelf ( 102 ). 
       FIG. 7 b    is an isometric schematic illustration of an illustrative, exemplary second embodiment, first variant of the utility corner shelf bracket  100   c , according to the present invention. 
       FIG. 7 c    is a top view schematic illustration of an illustrative, exemplary second embodiment, second variant of the utility corner shelf bracket  100   c , and two inserts  80 , according to the present invention, upon which the section plane  7   f - 7   f  is marked. 
     In this configuration, no nail  18  is permanently attached to a first bow wing  11   b . The attachment to a corner wall  101  (not shown in the present drawing) can be done by means of nails  18  connected to insert  80  or by means of an adhesive layer  18   b  (not shown in the preset drawing), which is upon an insert  80  that is free of nails  18 . 
     A user assembling the second embodiment, second variant of the utility corner shelf bracket  100   c  can choose the type of insert  80  suitable for attachment to the corner wall  101  according to the type of wall. Each one of the first bow wings  11   b  can be mounted with an insert  80  which can be removed and replaced with another insert  80  as necessary. 
     Even though the present invention mentions only two means for mounting insert  80  to a surface such as a wall, the present invention is in no way limited to these specific two means. Likewise, an insert  80  can include both nails  18  and an adhesive layer  18   b  (not shown in the present drawing). 
     The pulling assembly  20  is connected to second bow  12  which is connected to both first bow wings  11   b  which are connected to first bow arc  11   a.    
     The utility corner shelf bracket  100   c  includes a pulling assembly  20  as described in  FIG. 7 a   , however, the present invention is in no way limited to pulling assembly  20 , and other variations and types of pulling assemblies. 
       FIG. 7 d    is a top view schematic illustration of an illustrative, exemplary second embodiment, second variant, of the utility corner shelf bracket  100   c  and two inserts  80 , according to the present invention. 
     In the present illustration, an insert  80  equipped with nails  18  is mounted on one of the first bow wings  11   b  of the utility corner shelf bracket  100   c  and facing the second first bow wings  11   b , is disposed an insert  80  without nails  18 . 
     The first bow wings  11   b  and the inserts  80  are configured so that the insert outer surface  85  practically creates a unified surface with the first bow wing outer surface  11   bd , or as another possibility, the outer surface  85  slightly protrudes, relative to the dimensions of the inserts  80 , in order to enable good adhesion to the wall if the attachment to the wall is by means of adhesive. In the configuration shown in the present illustration each one of the inserts  80  has an insert body  81 , from which four elastic insert arms  82  protrude, at the end of each of which is an insert push button  83 , however according to the present invention, other configurations of inserts  80  are also possible. 
       FIG. 7 e    is an isometric view schematic illustration of an illustrative, exemplary second embodiment, second variant of the utility corner shelf bracket  100   c  and two inserts  80 , according to the present invention. 
     In the present illustration an insert  80  equipped with nails  18  is mounted on one of the first bow wings  11   b  of the utility corner shelf bracket  100   c  and facing the second first bow wings  11   b  is disposed an insert  80  without nails  18 . In this state, the illustration shows two first bow windows  11   bc . In the configuration shown in the present illustration, each one of both first bow wings  11   b  has four first bow windows  11   bc , the shape and location of which correspond with those of the insert arms  82  for the purpose of engagement with each other during assembly. 
     The insert  80  without nails  18  includes an adhesive layer  18   b  shown in the present illustration, for the purpose of visualization, with the adhesive layer  18   b  separated and disposed facing the insert body  81 . 
       FIG. 7 f    is a schematic cross sectional view  7   f - 7   f  of the utility corner shelf bracket  100   c  and of an insert  80 , according to the present invention. 
     The illustration marks detail A in a circle, which is magnified in the circle on the left side of the illustration. In the configuration shown in the present illustration, nails  18  are permanently fixed in the insert body  81 . The insert arm  82  is disposed within a first bow window  11   bc  while a first bow flap  11   bb  prevents undesired separation of the insert arm  82 , by means of an insert stair  84 , which is part of the shape of the insert push button  83 , which is leaning on it. In order to enable separation, the insert push button  83  must be pressed in the direction demonstrated by the pressing force F 5  arrow. 
       FIG. 7 g    is a top view schematic illustration of an illustrative, exemplary embodiment, of two inserts  80 , according to the present invention. 
     One of the two inserts  80  has nails  18  the other one has an adhesive layer  18   b.    
     From the insert body  81  an elastic insert back rail  88  and elastic insert arms  82  protrude backward, while at their edges are disposed the insert push buttons  83 . 
     The insert back rail  88  grants insert  80  mechanical strength and improves its grip of utility corner shelf bracket  100   c  (not shown in the present drawing), if both have shapes that conform to each other. 
     In the configurations shown in the present illustration, all components of each insert  80  are made as a single part of a uniform material, other than nails  18  and adhesive layer  18   b , however, according to the present invention, other configurations are also possible. 
       FIG. 7 h    is an isometric view schematic illustration of an illustrative, exemplary embodiment, of two inserts  80 , according to the present invention. 
     One of the two inserts  80  has nails  18  and the other one has an adhesive layer  18   b . At each of both distant ends of insert  80 , an insert outer side wall  87   a  protrudes backward from the insert body  81 . In insert body  81 , on the side wall facing the front, there can be an insert area  81   a  designated for partially containing an adhesive layer  18   b , such that it protrudes slightly from the insert  80  toward the front. 
       FIG. 7 i    is a front view schematic illustration of an illustrative, exemplary embodiment, of two inserts  80 , according to the present invention. 
     One of the two inserts  80  has nails  18  and the other one has an adhesive layer  18   b . In the configuration shown in the present illustration, in a view from the front, each insert push button  83  slightly protrudes from the boundaries of the insert body  81 , however other configurations are also possible according to the present invention. 
       FIG. 7 j    is a back view schematic illustration of an illustrative, exemplary embodiment, of an insert  80 , according to the present invention. 
     Parallel to each insert outer side wall  87   a  is an insert inner side wall  87   b , while between every pair of an insert outer side wall  87   a  and an insert inner side wall  87   b  are disposed two insert nail housings  86 . Each one of the nails  18  (not shown in the present drawing), is partially and permanently disposed within an insert nail housing  86 . 
     The insert outer side walls  87   a  and the insert inner side walls  87   b  grant insert  80  mechanical strength and improve its grip of utility corner shelf bracket  100   c , if it has a suitable, conforming shape. 
       FIG. 7 k    is a side view schematic illustration of an illustrative, exemplary embodiment, of two inserts  80 , according to the present invention. 
     The illustration marks detail C in a circle, which is magnified in the circle on the left side of the illustration, which also shows inserting means  89 . 
     One of the two inserts  80  has nails  18  the other one has an adhesive layer  18   b . The insert outer side wall  87   a , protruding from the insert body  81 , is disposed between two insert arms  82 . Each insert arm  82  has an insert push button  83  and an insert stair  84 . For every pair of adjacent insert stairs  84 , each insert stair  84  is facing outward, in an opposite direction. In order to remove an insert  80  from a utility corner shelf bracket  100   c  (not shown in the present drawing), each pair of insert push buttons  83  should be pressed inward, and then the insert  80  can be removed forward. 
     The adhesive layer  18   b  protrudes slightly forward from the insert outer surface  85 . This protrusion can be at an order of magnitude of parts of a millimeter. The adhesive layer  18   b  can be made of adhesive applied to a sheet or in some other configuration to the insert outer surface  85 , which can be covered with a protective sheet that is removed prior to performing attachment, for the purpose of preventing the adhesive from drying. 
     Even though the illustrations of the present application describe the structures of the inserts  80  in high detail, the present invention is in no way limited strictly to these structures, and according to the present invention, other structures are possible according to the present invention to fill the same functions. 
     The inserting means  89  includes the insert arm  82 , the insert push button  83 , and the insert stair  84 , shown in the present illustration, however the present illustration is not limited to only one type of inserting means  89 . 
       FIG. 8 a    is a top schematic illustration of an illustrative, exemplary third embodiment, first variant, of a utility corner shelf bracket  100   f , according to the present invention. 
     The utility corner shelf bracket  100   f  is made, possibly not including the nails  18 , as a one integral piece of an elastic material. 
     The third embodiment of a utility corner shelf bracket  100   f  does not have any pulling assembly and the forces attaching it to the walls come from the elasticity of the first bow  11 , having a first bow arc  11   a , and the second bow  12 , which are, for all practical purposes, springs. 
     Compression prior to mounting in a wall corner is done by means of pressing two pressing handles  36 . When the dimensions of the third embodiment of a utility corner shelf bracket  100   f  are sufficiently small, the compression can be done with one hand. Likewise, the third embodiment of a utility corner shelf bracket  100   f  can also include a hanging device  37 , to which one can, for example, tie a string with a balloon on its end. 
     The second bow  12  has two ends, a first end of a second bow  12   a , and a second end of a second bow  12   b , while each end is disposed directly to the end of each of the two first bow wings lib or to one of the two pressing handles  36 , while both options are acceptable and efficient. 
     The state shown in the present illustration is a free state, namely, there is no influence of any external forces on the utility corner shelf bracket  100   f  (third embodiment), and its shape is determined by the equilibrium of the internal elastic forces. 
     The first bow  11 , which is a spring, as noted, is bent in the free state bow arc bending angle ‘C’, the value of which is smaller than 90 degrees, while the second bow  12 , which is also a spring, as noted, is bent at second bow bending angle ‘D’. It has been determined that for the purpose of effective functioning of the utility corner shelf bracket  100   f  (third embodiment), the angle ‘D’ must be larger than a value suitable for a given model of utility corner shelf bracket  100   f  according to its structure and its composing materials. A typical value is bending of 40 degrees. 
     The present illustration shows that strengthening ribs  30  can have a suitable shape and dimensions to serve as buffers preventing excessive compression of the sixth embodiment of a utility corner shelf bracket  100   f . The third embodiment of a utility corner shelf bracket  100   f  can be composed of a single part and of a single material, without any moving parts, namely without any hinges or the like, and it can be manufactured in an injection process, without any connection means such as adhesives, welding, screws, etc. between its various parts. 
     However, there is an advantage that the nails  18  be composed of a rigid material, for example a metal, and be connected to an assembly that is cast at a later stage. In this configuration as well, the third embodiment of a utility corner shelf bracket  100   f  has no connection means such as adhesives, welding, screws, etc. between its various parts. 
     Good materials for the production of a third embodiment of a utility corner shelf bracket  100   f  can be selected from the group of polymers. 
       FIG. 8 b    is an isometric schematic illustration of an illustrative, exemplary third embodiment, first variant, of the utility corner shelf bracket  100   f , according to the present invention. 
       FIG. 8 c    is a top schematic illustration of an illustrative, exemplary third embodiment, first variant, of the utility corner shelf bracket  100   f , installed in a corner wall  101  upon which is mounted a corner shelf  102 , according to the present invention. 
     Corner shelf  102  can be transparent, as shown in the present illustration, or opaque. The corner wall  101  shown in the present illustration has an angle of practically ninety degrees, and the corner shelf bracket  100   f  was mounted into the corner after it was sufficiently compressed from its released mode, and after being placed next to the corner wall  101 , opened and latched into place by means of its elasticity. 
       FIG. 8 d    is an isometric schematic illustration of an illustrative, exemplary third embodiment, first variant, of the utility corner shelf bracket  100   f  which is attached to a load  40 , according to the present invention. 
     Load  40 , in the case of the present illustration, is a string and an attached balloon which is filled with a gas lighter than air so that it floats upwards. Load  40  can also be heavier than air, and can include various different means, such as string, chains, or hooks, for connection to the utility corner shelf bracket  100   f . The connection can be to hanging device  37  as well as to other locations of the utility corner shelf bracket  100   f.    
       FIG. 8 e    is an isometric schematic illustration of an illustrative, exemplary third embodiment, second variant, of the utility corner shelf bracket  100   f  having a nail protector  50 , according to the present invention. 
     In order to reduce the risk of injury from a nail  18 , the utility corner shelf bracket  100   f  can be equipped with nail protectors  50 , one of which is shown in the present illustration. 
     The illustration marks detail B in a circle, which is magnified in the circle on the upper side of the illustration, which also shows the nail protector  50 . 
     Nail protector  50  is connected to first bow wing  11   b  by means of a protector connector  50   a , which is thin relative to the thickness of the first bow wing  11   b , enabling bending and shifting the protector connector  50   a  from an open state, as shown in the present illustration, to a closed state (by rotational movement as indicated by an arrow in the illustration), in which the protector connector  50   a  covers nails  18 . 
     The protector connector  50   a  can also be equipped with a protector pin  50   b , which in a closed state will be inserted into a first bow wing hole  50   c , in which it will be held by forces of friction, until force is applied to release it. 
       FIG. 8 f    is a top schematic illustration of an illustrative, exemplary third embodiment, third variant, of the utility corner shelf bracket  100   f , having a protective wing  60  in open state, according to the present invention. 
     The third embodiment, third variant, of the utility corner shelf bracket  100   f , including all of the components described with regard to  FIG. 11 a   , namely to the sixth embodiment, first variant, of the utility corner shelf bracket  100   f , namely it includes the first bow  11 , having a first bow arc  11 , and tow first bow wings  11   b , the second bow  12  having two ends, a first end of a second bow  12   a , and a second end of a second bow  12   b , the two pressing handles  36 , the hanging device  37 , and the nails  18 . 
     Furthermore, the sixth embodiment, third variant, of the utility corner shelf bracket  100   f  includes two protective wings  60 , and two protective wing supports  61 . 
     The protective wings  60  are meant to shield from damage that can be caused to humans, animals, and inanimate objects as a result of contact with nails  18 . 
     Each protective wing  60  is connected to the first bow  11  at the protective wing connecting end  60   b . The connection can be by various means, such as by means of a shaft, an elastic connection, or any other suitable connection, while it is preferable for the connection to be such that will generate a moment driving the protective wing  60  toward a first bow wing  11   b . In the open state shown in the present illustration, each protective wing  60  is supported toward a protective wing support  61  and protects from contact with nails  18 . 
     Each protective wing support  61  is connected at a protective wing support first end  61   a  to one of the two pressing handles  36 . 
       FIG. 8 g    is a top schematic illustration of an illustrative, exemplary third embodiment, third variant, of the utility corner shelf bracket  100   f , having a protective wings  60  in closed state, according to the present invention. 
     In this state, each protective wing support  61 , which is made of elastic material, is within a pressing handle groove  36   a , and it is impossible to see neither the protective wing supports  61  nor the pressing handle grooves  36   a.    
     Each one of the protective wings  60  is now pressed to one of the first bow wings  11   b  and the nails  18  are exposed, a state which is suitable for attachment to the wall. 
       FIG. 8 h    is an isometric schematic illustration of an illustrative, exemplary third embodiment, third variant, of the utility corner shelf bracket  100   f , having a protective wings  60  in open state, according to the present invention. 
     The present illustration also clearly shows both pressing handle grooves  36   a , one in each pressing handle  36 , as well as the manner in which a protective wing supports  61  protective wing support first end  61   a  to a pressing handle  36 , and supports a protective wing  60 . 
     Likewise the present illustration shows protective wing holes  60   a  enabling the passage of nails  18  through a protective wing  60 . 
       FIG. 8 i    is an isometric schematic illustration of an illustrative, exemplary third embodiment, fourth variant, of a utility corner shelf bracket  100   f , having two nail shields  70  in a protective state according to the present invention. 
     The two nail shields  70  prevent undesired human contact with the nails  18 . This is a state suitable for storage of the utility corner shelf bracket  100   f  prior to use. 
       FIG. 8 j    is an isometric schematic illustration of an illustrative, exemplary third embodiment, fourth variant, of the utility corner shelf bracket  100   f , having two nail shields  70 , in a nails exposed state according to the present invention. 
     The utility corner shelf bracket  100   f  is also in this state when it is connected to a corner wall  101  (not shown in the present drawing). In this state, the nail shields  70  aren&#39;t disrupting the exposure of nails  18 . 
       FIG. 8 k    is an isometric schematic illustration of an illustrative, exemplary third embodiment, fourth variant, of the utility corner shelf bracket  100   f , having two nail shields  70 , in an immediately after molding state according to the present invention. 
     This state is achieved immediately after casting in the production process of the utility corner shelf bracket  100   f  and prior to its protective state. 
     Each one of the two nail shields  70  has a shield front wall  71  which is connected to two shield side walls  72 . On each shield side wall  72  there is a side wall slot  72   a.    
     Each shield front wall  71  is connected to a first bow wing  11   b  by means of a shield arm  73  one end of which is connected to a first integral pivot  73   a  and the other end of which is connected to a second integral pivot  73   b.    
       FIG. 8 l    is a top view schematic illustration of an illustrative, exemplary third embodiment, fourth variant, of the utility corner shelf bracket  100   f , having two nails shields  70 , in an immediately after molding state according to the present invention. 
     The illustration marks detail C in a circle, which is magnified in the circle on the lower side of the illustration. The present illustration shows no nails  18 , which can be assembled, according to the present invention, at a later stage of production. 
     In order to shift the utility corner shelf bracket  100   f  from the immediately after molding state to a protective state, a moment must be activated to cause angular movement in the direction shown by arrow α, the center of which is second integral pivot  73   b  of the nails shield  70  relative to the shield arm  73 . Furthermore, a moment must be activated to cause angular movement in the direction shown by arrow β, the center of which is the first integral pivot  73   a  of the shield arm  73  relative to the first bow wing  11 . Likewise, the elastic shield side wall  72  should be tilted in a direction perpendicular to the illustration sheet, and released at a position ensuring that a first bow first pin  11   e  is inserted into the side wall slot  72   a . The same should be done for the concealed shield side wall  72  not shown in the present illustration. 
     Once the first bow first pins  11   e  are within the side wall slots  72   a , they prevent the nail shields  70  from returning to the immediately after molding state that would occur due to the elastic qualities of the utility corner shelf bracket  100   f.    
     The first bow second pin  11   f  is located such that in certain states, it will prevent movement of the nail shield  70  when it meets with the shield stair  74 . 
     As used herein in the specification and claims sections, the term ‘integral pivot’ refers to a device that enables performance of repeated angular movements with at least two components connected to it, with which it composes a single integrated part, which can be made of a uniform material. 
       FIG. 8 m    is a top view schematic illustration of an illustrative, exemplary third embodiment, fourth variant, of the utility corner shelf bracket  100   f , having two nails shields  70 , in a protective state according to the present invention. 
     The first bow first pins  11   e , when engaged with the side wall slots  72   a , prevent the utility corner shelf bracket  100   f  from returning to the immediately after molding state. The shape of the side wall slot  72   a  is not limited to that of an arc as shown in the present illustration, and it can be shaped as any other orifice, as long as it fills its purpose as described so far. 
     When a force F 6  is applied on the nails shield  70  as shown in the present illustration, for example by a finger, the nails shield  70  moves toward the first bow wing  11   b.    
       FIG. 8 n    is a top view schematic illustration of an illustrative, exemplary third embodiment, fourth variant, of the utility corner shelf bracket  100   f , having two nail shields  70 , in a safe state according to the present invention. 
     The continued activation of the force F 6  causes further movement of the nails shield  70  until it stops as a result of contact of the shield stair  74  with the first bow second pin  11   f . In this state, if the force F 6  is generated by the pressure of a finger, the finger will not be injured seeing as the nails  18  are not exposed but rather contained within the nails shield  70 . 
       FIG. 8 o    is a top view schematic illustration of an illustrative, exemplary third embodiment, fourth variant, of the utility corner shelf bracket  100   f , having two nails shields  70 , in a press against corner walls  101  state, according to the present invention. 
     Prior to installation of the utility corner shelf bracket  100   f  on corner walls  101 , the user presses the pressing handles  36  so that they draw close to each other, and disposes the utility corner shelf bracket  100   f  as close as possible to the designated place of installation, so that both the nail shields  70  are in contact with the corner walls  101 . 
     In the next stage, the user releases the force from the pressing handles  36 , and thanks to the elasticity of the first bow wing  11   b  and of the second bow  12 , pressure forces of the corner walls  101  are generated upon the nails shields  70 , causing them to move relative to the remaining components of the utility corner shelf bracket  100   f , and unlike the movement described in the previous illustration and accompanying description, the movement of each one of the nail shields  70  in the state shown in the present illustration does result in the exposure of the nails  18 , subsequently enabling contact of the nails  18  with the corner walls  101  and even penetration. 
       FIG. 8 p    is a top view schematic illustration of an illustrative, exemplary third embodiment, fourth variant, of the utility corner shelf bracket  100   f , having two nails shields  70 , in an installed on a corner walls  101  state according to the present invention. 
     In this state, the shield front walls  71  are attached to the corner walls  101  and the nails  18  penetrate them. 
     While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention may be made.