Abstract:
A welding rod container includes a rectangular body, and a unitary rectangular metal end having: a permanent portion secured at its outer edge to the body and having a flange terminating inwardly in a double-bend portion, the double-bend portion including an inwardly-extending lowermost level; and a removable portion having a peripheral edge joined to the lowermost level of the double-bend portion at a tear-line, the lowermost level and peripheral edge having first and second offset levels, the tear-line being formed by the offset juncture thereof.

Description:
FIELD OF THE INVENTION  
       [0001]     The invention relates generally to containers having end portions sealed to corresponding container bodies and, more particularly, to welding rod containers with metal ends.  
       BACKGROUND  
       [0002]     Welding rods may be used in various types of welding including, for example, their use with conventional electric welders, sometimes referred to as stick welders, where welding may be performed by creating an electric arc between the end of a welding rod and the work piece or work pieces. Various other welding and bonding processes may utilize welding rods, such as processes that inject additional materials into a welding location for improving efficiency, lowering cost, removing/preventing impurities, etc. Welding rods may contain a flux or flux generating material covering a metal rod for preventing oxidation of the welding rod material and areas adjoining the work piece. The rods may contain other additives, depending on the particular welding application.  
         [0003]     A welding operator may elect to use any of several different welding rod sizes and materials, depending on the job being performed, cost considerations, etc. For example, the operator may choose to weld thin material one minute and thick material the next, changing welding rods as to material or size as appropriate for welding different pieces. Such different size welding rods, that may be formed of different materials, are typically provided in separate containers.  
         [0004]     It is often desirable to prevent welding rods from being exposed to water, air, and other impurities in order to prevent oxidation and lowering of welding efficiency and quality. Therefore, welding rods are typically provided in sealed containers that can include, for example, a cover for re-sealing the container after it has been opened. However, conventional welding rod containers do not optimize a so-called “easy-open” structure, and do not optimize welding rod container safety to address concerns such as the possibility of an operator&#39;s hand being cut on a sharp exposed edge created when opening an easy-open welding rod container.  
         [0005]     For example, the operator may position an opened welding rod container near a welder and then insert his hand into the opened container to retrieve a welding rod. In doing so, the operator may be wearing a welding shield and may have his attention directed to other matters, whereby he may inadvertently risk being cut by a sharp fractured score-line of a conventional easy-open container.  
       OBJECTS OF THE INVENTION  
       [0006]     It is an object of the invention to provide an improved welding rod container overcoming some of the problems and shortcomings of the prior art, including those referred to above.  
         [0007]     Another object of the invention is to provide an easy-open container allowing a cooperation of structural elements for optimizing an ease of opening the container.  
         [0008]     Another object of the invention is to provide an easy-open welding rod container with a reduced risk of hand contact with a sharp edge when a user reaches into the opened container.  
         [0009]     Still another object of the invention is to provide a pull-tab type easy-open container allowing a cooperation of structural elements for reducing the amount of sharp edge exposure created by opening the container.  
         [0010]     Yet another object of the invention is to provide a simple welding rod container form that allows for easy manufacturing thereof.  
         [0011]     How these and other objects are accomplished will become apparent from the following descriptions and the drawings.  
       SUMMARY OF THE INVENTION  
       [0012]     According to an aspect of the invention, in a welding rod container of the type including (a) an elongate container body of rectangular cross-section and terminating at an open-end edge, (b) a metal end having a permanent portion with a rectangular outer edge secured to the open-end edge of the body and a removable portion defined by a tear-line, and (c) a pull-tab on the removable portion for manual fracture of the tear-line and removal of the removable portion to open the container, an improvement includes: the permanent portion of the metal end having a double-bend portion as an innermost blunt edge, the double-bend portion serving to recess the tear-line and removable portion, the tear-line being positioned such that it is away from hand contact when a user reaches into the opened container; and, the tear-line extending around the pull-tab and from there, on either side of the pull-tab, across the metal end in directions diverging from adjacent outer edges of the metal end, whereby such double-bend portion and tear-line cooperate for easy opening and edge safety.  
         [0013]     According to another aspect of the invention, a welding rod container includes a rectangular body, and a unitary rectangular metal end having: a permanent portion secured at its outer edge to the body and having a flange terminating inwardly in a double-bend portion, the double-bend portion including an inwardly-extending lowermost level; and a removable portion having a peripheral edge joined to the lowermost level of the double-bend portion at a tear-line, the lowermost level and peripheral edge having first and second offset levels, the tear-line being formed by the offset juncture thereof.  
         [0014]     According to a further aspect of the invention, a welding rod container includes a container body of a size at least as long as a welding rod to be contained therein, and a unitary rectangular metal end including: a permanent portion secured at its outer edge to the body and having an inwardly-extending flange; and, a removable portion having a peripheral edge joined to the inwardly-extending flange at a tear-line, where the inwardly-extending flange of the permanent portion and the peripheral edge of the removable portion have respective first and second offset thicknesses, the tear-line being formed by the offset juncture thereof.  
         [0015]     As a result of the present invention, structural portions of a welding rod container combine in cooperative fashion to assist the ease of opening the container. In addition, safety is improved as a result of less exposure of potential sharp edges.  
         [0016]     The foregoing summary does not limit the invention, which is instead defined by the attached claims. 
     
    
     BRIEF DESCRIPTION OF THE DRAWING FIGURES  
       [0017]      FIG. 1  is a perspective view of a welding rod container according to an exemplary embodiment of the subject invention.  
         [0018]      FIG. 2  is a perspective view of a metal end portion of the welding rod container of  FIG. 1 .  
         [0019]      FIG. 3  is a top plan view of the metal end portion of  FIG. 2 , minus the pull-tab.  
         [0020]      FIG. 4A  is a top plan view of a pull-tab of the metal end portion of  FIG. 2 , and  FIG. 4B  is an enlarged fragmentary plan view of a piercing end of the pull-tab of  FIG. 4A .  
         [0021]      FIG. 5  is a side plan view of the pull-tab of  FIG. 4A .  
         [0022]      FIG. 6  is a cross-sectional view taken along the line A-A of  FIG. 5 .  
         [0023]      FIG. 7  is a fragmentary cross-sectional view of the metal end portion of  FIG. 3 , taken along the pulling tab lengthwise axis thereof.  
         [0024]      FIG. 8  is a fragmentary cross-sectional view of the tear-line of the metal end portion of the welding rod container of  FIG. 1 .  
         [0025]      FIG. 9  is a fragmentary cross-sectional view of a metal end portion having a tear-line disposed inwardly of a double-bend portion and having a seam joining the metal end portion to the main container portion, according to an exemplary embodiment of the invention.  
         [0026]      FIG. 10  is a fragmentary cross-sectional view of a metal end portion having a tear-line disposed outwardly of the inner perimeter blunt edge of a double-bend portion thereof and having a flange type outer perimeter, according to an exemplary embodiment of the invention.  
         [0027]      FIG. 11A  is a top plan view of a metal end portion having an outer flange type perimeter, for example having a structure as shown in  FIG. 10 ;  FIG. 11B  is a side plan view of the metal end portion of  FIG. 11A . 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0028]     FIG. is a perspective view of a welding rod container  10  according to an exemplary embodiment of the invention. Container  10  has an elongated main container portion  12  having a length greater than a length of welding rods to be held therein. Main container portion  12  may be formed of any suitable durable, air-tight, water-tight material such as metal, resin, and others. Main container portion  12  preferably has an even and level upper edge  13  that may include a flat, flanged, or other shaped surface, and that provides the perimeter of an open end thereof. Such upper edge  13  provides a location for attaching main container portion  12  to a metal end portion  14 .  
         [0029]      FIGS. 2-7  show an exemplary metal end portion  14  of welding rod container  10 . Metal end  14  preferably has a square shape but any other appropriate shape, corresponding to a shape of the open end of main container portion  12 , may be used. Metal end  14  is formed of a thin unitary metal sheet  21 , a pull-tab  31 , and a rivet  37  for attaching the pull-tab  31  to the sheet  21 .  
         [0030]     Metal end  14  has a permanent portion  22  and a temporary portion  23  enclosed by permanent portion  22  along a tear-line  41 . The outer perimeter of permanent portion  22  has a horizontal flange  24 . Flange  24 , as discussed further below, may also be referred to as a “seaming panel.” A vertical portion  25  of metal end  14  is formed at the inner perimeter of the square formed by flange  24  as the result of a bend  26  of ninety degrees having a radial curvature. Vertical portion  25  extends to a lower radial bend  27  of ninety degrees that redirects sheet  21  of permanent portion  22  inwardly to form a middle portion  28  that is essentially in parallel with flange  24  and that provides the flat top surface of the permanent portion  22 .  
         [0031]     Middle portion  28  extends inwardly to a double-bend portion  61  that includes a first 180 degree bend  64 , a second 180 degree bend  65 , and a middle portion therebetween. After second bend  65 , double-bend portion  61  extends inwardly as a permanent end portion  66  that terminates at tear-line  40 . Tear-line  40  is formed by the offset relation of two levels  44 ,  45  of sheet  21 , at a location where permanent end portion  66  joins temporary peripheral portion  67 . Tear-line  40  is preferably located proximate the inner peripheral blunt edge  62  formed at the apex of first bend  61 , as shown by example in  FIG. 9  being formed slightly inwardly of blunt edge  62 , and as shown in  FIG. 10  being formed slightly outwardly of blunt edge  62 .  
         [0032]     Tear-line  40  defines the juncture between temporary portion  23  and permanent portion  22 . Tear-line  40  preferably forms such juncture as a diamond-shaped line when viewed from above as shown in the top plan illustration of  FIG. 3 . Tear-line  40  can be seen as having four rounded corners  46 ,  47 ,  48 ,  49 , where corner  46  is proximate pull-tab  31 . As the routes of tear-line  40  lead from corner  46  on either side of pull-tab  31 , tear-line  40  diverges away from respective adjacent container sides  71 ,  72  between corner  46  and corners  47 ,  49 . The respective routes of tear-line  40  from corners  47 ,  49  to corner  48  then converge toward respective sides  73 ,  74  of container  10 .  
         [0033]     A moustache score  81  is formed in temporary portion  23  adjacent rivet  37  and perpendicular to lengthwise tab pulling axis  32 . The pointed end portion  33  of pull-tab  31  may be positioned so as to abut both the adjacent double-bend portion  61  and tear-line  40 . Metal sheet  21  in the area  82  of temporary portion  23  under pull-tab  31  may be formed as a raised portion  83  where rivet  37  does not extend inside main container portion  12 .  
         [0034]     A raised panel  90  is formed as an island type structure in temporary portion  23 . Although shown as a raised panel, the panel  90  may alternatively be formed as a recessed panel. An embossed logo  85  or other indicia may be stamped, engraved, or otherwise formed on raised panel  90 . Raised panel  90  has a side formed essentially perpendicular to lengthwise tab pulling axis  32 . The remainder of the perimeter of raised panel  90  is formed to be essentially in parallel with the respective adjacent parts of tear-line  40 . For example, side  91  of raised panel  90  is essentially in parallel with side  55  of tear-line  40 , side  92  of raised panel  90  is essentially in parallel with side  56  of tear-line  40 , and short intermediate sides  93 ,  94  of raised panel  90  are essentially in parallel with respective adjacent tear-line portions  57 ,  58 .  
         [0035]     Pull-tab  31  has a pointed end section  33  adapted for piercing tear-line  40  near corner  46  when tab  31  is pulled upwardly in a conventional manner. Pull-tab  31  has a middle section  34  secured to a slightly raised section  83  of temporary portion  23  with rivet  37  passing through hole  36  of middle section  34 . Middle section  34  is at a slight angle with respect to pointed end section  33 . A pulling portion  35  of pull-tab  31  is slightly angled with respect to middle section  34  and has a center opening  38  adapted for receiving a user&#39;s finger under a rounded part  39  of a lateral section  30 .  
         [0036]      FIGS. 9 and 10  show variations and options that may be chosen for a particular welding rod container application. By comparison,  FIG. 9  shows a tear-line  41  located inwardly of blunt edge  62  formed on the inner perimeter of double-bend portion  61 , whereas  FIG. 10  shows a tear-line  51  disposed outwardly of blunt edge  62 . In addition, seaming panel  24  of  FIG. 9  is formed into a seam along with an outermost edge  16  of main container portion  12 . Such seam may be formed to be airtight and watertight in a known manner including, but not limited to, use of sealants, welding, pressure, tension, etc. By comparison, flange  29  of  FIG. 10  may be kept in a horizontal configuration, either having a single layer as shown, or doubled back upon itself after abutting engagement with a corresponding flange (not shown) of main container portion  12 , thereby forming a double-layer horizontal flange  29  that encloses the flange of end  16  of main container portion  12 . Such an embodiment is shown by example in  FIGS. 11A and 11B , which also illustrate a curved side  95  of a raised panel  96 , which provides a similar cooperation with other container structure, while effecting a different profile for transfer of pulling force.  
         [0037]     A sealing compound  75  is used for assuring the watertight sealing between metal end portion  14  and main container portion  12 . Vertical portion  25  may also be bonded to main container portion  12 . Sealing compound  75  may be placed along the under side of flange/sealing panel  29 , at the juncture of flange  29  and vertical portion  25 , and/or along vertical portion  25 . Then, the forming of a seam and/or other sealing type bonding between main portion  12  and end  14  is performed.  
         [0038]     In various applications, a seal between the metal end  14  and the main container portion may also be made by use of an adhesive, heat, sonic heating, high-frequency heating, or by heating the main container portion  12  (if it is metal) using electrical induction or by local direct heat application.  
         [0039]     In forming welding rod container  10 , tear-line  40  may be created by a precise partial shearing or by a stamping operation that creates the boundary  58  between temporary and permanent portions,  23 ,  22 , respectively. Such boundary  58  preferably has a vertical thickness from twenty to fifty percent of the nominal thickness  59  of metal sheet  21 , depending on the particular material being used. An optimum thickness of the boundary  58  should be large enough to prevent the possibility of unwanted tearing and small enough to allow easy tearing when pull-tab  31  is pulled.  
         [0040]     A welding technician may open welding rod container  10  by holding the container  12  with one hand and placing one or more fingers of the other hand under rounded part  39  of lateral section  30 . The technician then lifts pull-tab  31  first upwardly so that lateral section  30  is being moved toward corner  46 , whereby pointed end  33  of pull-tab  31  pierces tear-line  40 . The piercing movement is enabled by rivet  37  acting as a fulcrum and by moustache score  81  acting to concentrate the piercing force toward tear-line  40 .  
         [0041]     When pull-tab  31  is approximately vertical and corner  46  has been pierced, the technician then pulls pull-tab  31  away from corner  46 . In doing so, tear-line  46  proceeds to fracture as it diverges laterally from the respective sides  71 ,  72  of container  10 . Side  98  of raised panel  90 , being perpendicular to tab pulling axis  32 , prevents the pulling force from deforming temporary portion  23 , so that the pulling force is instead directed outwardly to tear-line  40 . In addition, the relation of tear-line  40  and double-bend portion  61  acts to further direct the pulling force to tear-line  40 . Further, double-bend portion  61  also acts as a spring or cushion, to a degree dependent on various factors such as the material being used, the relative dimensions of double-bend portion  61 , etc. Such spring-like action serves as a buffer to prevent pulling force from being transmitted beyond the area near tear-line  40  and acts in cooperation with the tear-line offset form to provide easier and cleaner tearing.  
         [0042]     After temporary portion  23  has been removed and welding rods have been used, the technician may wish to reseal the container  10  to prevent intrusion of impurities such as water. Accordingly, a cover cap (not shown) may be provided for covering the opened metal end  14 . Such a cap may be formed of plastic, resin, fiber, and/or other material.  
         [0043]     The diamond shape of tear-line  40 , in combination with the configuration having adjacent sides  91 ,  92 ,  93 ,  94  of raised panel  90  being parallel with respective portions of tear-line  40 , also provides for easier removal of temporary portion  23  from permanent portion  22 . In a manner similar to other cooperating elements, such relationship between such sides of raised panel  90  and essentially parallel parts of tear-line  40  acts to prevent physical distortion of metal sheet  21  of temporary portion  23  and concentrates pulling force at tear-line  40 .  
         [0044]     Raised area  83  of temporary portion  23  under pull-tab  31  also acts to concentrate initial tab lifting force at the initial tearing point, especially when such structure is combined with adjacent structural configuration including rivet  37  acting as an ersatz fulcrum, moustache score line  81  acting to direct initial bending of adjacent areas of metal sheet  21  proximate rivet  37 , and structural integrity provided by raised panel  90 . Further, corners  18 ,  19  of metal end  14  are preferably formed to align with respective corners  49 ,  48  of tear line  40 , also adding structural support for a tearing operation.  
         [0045]     Protective compounds may be applied at either or both of upper surface  87  and/or lower surface  88  of metal sheet  21  in the immediate vicinity of tear-line  40 . When tear-line  40  fractures as a result of a welding technician removing temporary portion  23 , such protective compounds are caused to be displaced so that they cover at least a portion of the newly-created edge created by the fracture. Such compounds may become exposed by the fracturing process. The protective compounds act to provide additional protection against injury to the welding technician&#39;s hand due to possible contact with a sharp edge.  
         [0046]     The structural relationship between double-bend portion  61  and tear-line  40  provides additional safety against cuts and similar injuries. For example, when the fracture edge is created by tab-pulling force, the edge bends upwardly into a space under the inner peripheral blunt edge  62  of double-bend portion  61 , whereby a technician&#39;s hand is prevented from making contact with the fracture edge by blunt edge  62 . Such protection is increased when tear-line  51  is disposed slightly outwardly of inner peripheral blunt edge  62 , when a thickness  59  of metal sheet  21  is small, and/or when a thickness of vertical portion  58  of tear-line  40  is small, etc. When relative dimensions are made thinner, a large tab pulling force acts to further drive any exposed edge into the space under blunt edge  62 , but such thinner material may also cause a sharper fracture edge. By making the boundary  58  vertical thickness as small as practical, a corresponding vertical dimension of potential sharpness also becomes smaller.  
         [0047]     While the principles of the invention have been shown and described in connection with specific embodiments, it is to be understood that such embodiments are by way of example and are not limiting.